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| Distributed Cataloging on the Internet: the
| RePEc project
|
|
|
|
|
|
|
|
| Distributed Cataloging on the Internet: the
| RePEc project
|
| José Manuel Barrueco Cruz and Thomas Krichel
|
|
|
|
|
|
| Abstract
| Cataloging online documents requires a finer level of granularity
| than many other objects. Collecting that data is a costly process to
| achieve and manage. One possible approach towards cataloging these
| resources is to get a commonity of providers involved in cataloging the
| materials that they provide. This paper introduces RePEc of
| http://netec.wust.edu/RePEc, as an example for such an approach. RePEc is
| mainly a catalog of research papers in Economics. In May
| 1999, it is based on set of
| over 80 archives which all work independently but yet are interoperable.
| They together provide data about almost 60,000 preprints and over 10,000
| published articles. In principle each institution participating in RePEc
| provides its own papers by providing and maintaining an archive. The key
| issue of the paper is to evaluate the success of that decentralized
| approach in providing data of reasonable quality.
|
|
|
| José Manuel Barrueco Cruz is a librarian at the Universitat de
| València. Thomas Krichel is a lecturer in Economics at the University of
| Surrey. Both welcome comments on this paper, write to
| wopec@netec.mcc.ac.uk. This
| paper is available in
| PDF.
|
|
| 1: Introduction
| The electronic dissemination of Economics working papers can be traced back
| to the start of the Working Papers in Economics
| (WoPEc) project in April 1993. By
| May 1999 this single archive has grown into an interconnected network of
| over 80 archives holding over 14,000 downloadable working papers and over
| 50,000 descriptions of offline papers from close to 1,000 series. This is
| the largest decentralized collection of free online scientific documents in the
| world. The network of archives is called
| RePEc. This term is was initially
| conceived to stand for "Research Papers in Economics". Nowadays it is
| best understood as a literal, because the objectives of RePEc go way beyond
| a database of scientific papers. In Section 2
| we will introduce some of the broader aspects of RePEc.
| RePEc data is freely available, in the sense that the provider pays for the
| provision of the data, not the user. In order to make such a system viable
| without public subsidy, the cost of providing the data must be spread among
| many agents (understood here and in the rest of the paper as a
| person or institution). This requirement has been a feature of RePEc right
| from the start of the collection in May 1997. Each participating provider
| sets up an archive on a http or ftp server. The archive supports the
| storage of structural data about objects relevant to Economics, and
| possibly the storage of some of the objects themselves. All objects in
| RePEc are uniquely identified following by handles.
| RePEc data can be accessed through a plethora of user services. Some
| are heavily used, for example the "IDEAS"
| user service had one million hits in just over 2 moths in 1999.
| The main interest of this paper is to examine the collection aspect of the
| data. The idea that a coherent literature catalog can be put together by a
| large group of people who are physically dispersed and have very little
| personal commonication without the need of extensive training nor intensive
| coordination remains to be demonstrated. In May 1999,
| RePEc is two years old. We feel that this is a good time to review the
| operations of RePEc and the data that it has collected. Clearly the RePEc
| data is in a constant state of flux. To keep matters simple we took a dump
| of the data on 1 May 1999. In this paper only refer to the state
| of the data on that date.
| There are some aspects of RePEc that this paper does not discuss. We
| eschew any mentioning of the data on software, books, etc to concentrate on
| the collection of traditional academic papers be they preprints or
| published articles. This data forms the bulk of the present collection. We
| also leave out the personal and institutional data which are is not included in
| the papers and article templates. We aim to use such data to build a fully
| relational database system that describes Economics as a discipline. We
| will report on such efforts in future papers.
| In Section 3 we
| describe the setup of an individual archive through the use of an example. In
| Section 4 we look at the actual network of
| archives and the social fabric that supports them. In Section
| 5 we look at some aggregative aspects
| of the complete RePEc dataset.
| Section 6
| concludes this paper with an overall evaluation of the methods used by
| RePEc.
|
| 2: RePEc
| The nature of RePEc is not precisely defined. Most people
| think about it as a collection
| of archives and services that provide data about Economics.
| More precisely, RePEc is most commonly understood as referring to three
| things. First it is a collection of archives that provide data about
| Economics. Second it is the data that is found on these archives. Third, it
| is often also understood to represent the group of people who build archives
| and channel the data from the archives to the users. In that latter sense
| RePEc has no formal management structure.
| RePEc has two aims. The "cataloging aim" is to provide a complete
| description of the Economics discipline that is available on the Internet.
| The "publishing aim" is to provide free access
| to Economics resources on the Internet.
| The basic principle of RePEc can be summarized as follows Many archives
| ---> One
| dataset ---> Many services
|
| The basic RePEc concepts are: archive, site and service.
|
|
| An "archive" is a space on a public access computer system which makes data
| available. It is a place where original data enters the system. The is no need
| to run any software other than an ftp or http daemon that makes the files in
| the archive available upon request.
| A "site" is a collection of archives
| on the same computer system. It usually
| consists of a local archive augmented by frequently updated ("mirrored")
| copies of remote archives.
| A "service" is a rendering of RePEc data in a form that is available to
| the end user.
|
| All archives hold papers and metadata about papers, as well as software
| that is useful to maintain archives. Everything contained in an archive may
| be mirrored. For example, if the full text of a paper is in the archive, it
| may be mirrored. If the archive does not wish the full text to be mirrored,
| it can store the papers outside the archive. The advantage of this
| "remote storage" is that the archive maintainer will get a complete set
| of access logs to the file. The disadvantage is that every request for the
| file will have to be served from the local archive rather than from the
| RePEc site that the user is accessing. Of course an archive may also
| contain data about documents that are exclusively available in print.
| An obvious way to organize the mirroring process would be to mirror the
| data of all archives to a central location. This central location would in
| turn be mirrored to the other RePEc sites. The founders of RePEc did not
| adopt that solution, because it would be quite vulnerable to mistakes at
| the central site. Instead each site installs the mirroring software and
| mirrors "on its own", so to speak. Not all of them adopt the same
| frequency of updating. Many update every night, but a minority only updates
| every week. It is therefore not known how long it takes for a new item to
| be propagated through the system.
| There is no need for every site to mirror the complete contents of every
| archive in the system. To conserve disk space and bandwidth some sites only
| mirror bibliographic information rather than the documents that an archive
| may contain. Others mirror all the files of an archive. Others may mirror
| only parts of a few archives. The software that is used to mirror the
| archive is provided at RePEc:all. It first mirrors the central archive.
| This software then reads a configuration file and then writes batch calls
| to the popular "mirror" program for
| ftp and the "w3mir" script for
| http archives.
| Each service has its own name. A service that is based on mirrored scripts
| may run on many locations. Within reason, all services are free to use any
| part of the RePEc data as they see fit. For example a service may only
| show papers that are available electronically, others may restrict the
| choice further to act as quality filters. In this way services implement
| constraints on the data, whether they be availability constraints or
| quality constraints.
| There is no official list of all user services but
| http://netec.wustl.edu/WoPEc.html
| has a fairly comprehensive lists. The ability of RePEc to be used in many
| user services is its most important success feature. It is the single most
| important reason behind its success. However in this paper we will only
| concentrate on the quality of the data itself, rather than its implementation
| and use of user services.
|
| 3: The structure of an archive
| RePEc stands on two pillars. First, an attribute:value template
| metadata format called ReDIF. This acronym stands for Research
| Documentation Information Format but it is best understood as a
| literal. ReDIF defines a number of templates. Each templates describes an
| object in RePEc. It has a set of allowable fields, mandatory, and
| some repeatable. The second pillar is the Guildford protocol. It fixes
| rules how to store ReDIF in an archive. It basically indicates which files may
| contain which templates. It is possible to deploy ReDIF without using the
| Guildford protocol. But in the following we will ignore this conceptual
| distinction, because it is easiest to understand the structure and contents
| of an archive through an example. This is done in Subsection
| 3.1. Therefore we will list files in the way required
| by the protocol as well as the contents of the file that is in fact written
| in ReDIF. This is done in Subsection 3.1. We
| return to technical aspects of ReDIF in Subsection
| 3.2.
|
| 3.1: The Guildford Protocol
| RePEc identifies each archive by a simple identifier or handle. Here we look at
| the archive RePEc:sur which lives at
| ftp://www.econ.surrey.ac.uk/pub/RePEc/sur. On the root directory of the
| archive, there are two mandatory files. The file surarch.rdf contains a single
| ReDIF archive template.
|
| Template-type: ReDIF-Archive 1.0
| Name: University of Surrey Economics Department
| Maintainer-Email: T.Krichel@surrey.ac.uk
| Description: This archive provides research papers from the
| Department of Economics of the University of Surrey,
| in the U.K.
| URL: ftp://www.econ.surrey.ac.uk/pub/RePEc/sur
| Homepage: http://www.econ.surrey.ac.uk
| Handle: RePEc:sur
|
|
| In this file we find basic information about the archive. The other
| mandatory file is surseri.rdf. It must contain one
| or more series templates.
|
| Template-Type: ReDIF-Series 1.0
| Name: Surrey Economics Online Papers
| Publisher-Name: University of Surrey, Department of Economics
| Publisher-Homepage: http://www.econ.surrey.ac.uk
| Maintainer-Name: Thomas Krichel
| Maintainer-Email: T.Krichel@surrey.ac.uk
| Handle: RePEc:sur:surrec
|
|
| These two files are the only mandatory files in the Guildford
| protocol. If these are the only files present in the archive then all the archive
| is doing is to reserve the archive and the series codes. All documents have
| to be in a series. The papers for the series RePEc:sur:surrec are confined
| to a directory called surrec. It may contain files of any type. Any file
| ending in ".rdf" is considered to contain ReDIF templates. Let us
| consider one of them, surrec/surrec9601.rdf (We suppress
| the Abstract: field to conserve space.)
| Template-Type: ReDIF-Paper 1.0
| Title: Dynamic Aspect of Growth and Fiscal Policy
| Author-Name: Thomas Krichel
| Author-Email: T.Krichel@surrey.ac.uk
| Author-Name: Paul Levine
| Author-Email: P.Levine@surrey.ac.uk
| Author-WorkPlace-Name: University of Surrey
| Classification-JEL: C61; E21; E23; E62; O41
| File-URL: ftp://www.econ.surrey.ac.uk/pub/
| RePEc/sur/surrec/surrec9601.pdf
| File-Format: application/pdf
| Creation-Date: 199603
| Revision-Date: 199711
| Handle: RePEc:sur:surrec:9601
|
|
| Note that we have two authors here. The
| "Author-WorkPlace-Name" attribute only applies to the second author.
| We will come discuss this point now.
|
| 3.2: The ReDIF metadata format
| The ReDIF metadata format is mainly an extension of the
| Karlsson and Krichel
| (1999) commonly known
| as the IAFA templates. In particular it borrows the idea of clusters from
| the draft There are certain classes of data elements, such as
| contact information, which occur every time an individual, group or
| organization needs to be described. Such data as names, telephone numbers,
| postal and email addresses etc. fall into this category. To avoid repeating
| these common elements explicitly in every template below, we define
| "clusters" which can then be referred to in a shorthand manner in the
| actual template definitions. ReDIF takes a slightly different approach
| to clusters. A cluster is a group of fields that jointly describe a
| repeatable attribute of the resource. This is best understood by an
| example. A paper may have several authors. For each author we may have
| several fields that we are interested in, the name, email address, homepage
| etc. If we have several authors then we have several such groups of
| attributes. In addition each author may be affiliated with several
| institutions. Here each institution may be described by several attributes
| for its name, homepage etc. Thus a nested data structure is required. It
| is evident that this requirement is best served in a syntax that
| explicitly allows for
| it such as XML. However in 1997--when ReDIF was
| designed--XML was not available. We are still convinced that the
| template syntax is more human readable and easier understood. However the
| computer can not find which attributes correspond to the same cluster
| unless some ordering is introduced. Therefore we proceed as follows.
| For each group of arguments that make
| up a cluster we specify one attribute as the "key" attribute. Whenever
| the key attribute appears a new cluster is supposed to begin. For example
| if the cluster describes a person then the name is the key. If an
| "author-email" appears without an "author-name" preceding it
| the parsing software aborts the processing of the template.
| Note that the designation of key attributes is not a feature of ReDIF. It
| is a feature of the template syntax of ReDIF. It is only the syntax that
| makes nesting more involved. We do not think that this is an important
| shortcoming. In fact we believe that the nested structure involving the
| persons and organizations should not be included in the
| document templates. What should be done instead is to
| separate the personal information out of the document templates into
| separate person templates.
|
| 4: The archives
| The main issue of this paper is to evaluate if the decentralized collection
| of conventional bibliographic data works on the Internet. Given the
| requirements on the data that we have sketched in the previous section,
| will the staff at the providing institutions be able to supply it? This
| question is addressed in this section and in the next one.
| In order to understand how the archive work in practice,
| we look at the social structure
| supporting the archives.
| We set out our understanding about how archives are maintained internally and
| supported externally. In theory all providers are equal. They all read the
| same documentation; then they all register once with the same central archive
| etc. In practice some are more equal than others. These people are not only
| are involved in the operation of a local archive but they also
|
| act as consultants for the erection of new archives
| work on implementation software
| develop and maintain RePEc services
|
| For the purpose of this paper it is therefore useful
| to think about these persons as a small "RePEc team" whose members share
| roughly the same knowledge and enthusiasm. It consists of
|
| José Manuel Barrueco Cruz,
| Assistant Librarian, Universitat de
| València
| Christopher Baum, Associate Professor
| of Economics, Boston College
| Sune Karlsson,
| Assistant Professor, Stockholm School of Economics
| Thomas Krichel, lecturer in Economics, University of
| Surrey
| Sergei I. Parinov, Head of the Department for
| Information Technologies in the Economic System at
| Institute of Economics and Industrial Engineering of
| the Siberian Branch of the Russian Academy of Science
|
| Robert P. Parks, Professor of Economics,
| Washington University St. Louis
| Geoff Shuetrim, Researcher, Reserve Bank of
| Australia
|
| Christian Zimmermann,
| Assistant Professor of Economics, University of Québec at Montréal.
|
| The level of involvement of these persons varies. But for the
| purpose of this study these people are assumed to be equal. This
| assumption allows us to bring forward the following definition.
| We say that an
| archive is "controlled" if it is managed by a member of the RePEc team
| or managed by a person working under the supervision of a team member.
| The other archives will be called "loose" archives. These archives
| are not under the direct control of a member of the RePEc team.
| We will address the controlled and loose archive
| in Subsection 4.1
| and Subsection 4.3 respectively.
|
| 4.1: The controlled archives
| Within the controlled archives we distinguish five categories.
|
| "archives of controlled collections"
| bring together material
| collected from different sources. The data collection effort
| is made by a member of the RePEc team or an agent working directly
| under her control.
| "archives of hosted collections"
| combine material collected from different sources.
| The data collection effort is made by a person outside the RePEc team but
| the RePEc archive where the data is held in the form of ReDIF is on
| a disk to which a member of the RePEc team has write access.
| "archives of hosted sources"
| are archives for data from a single
| source that is provided by a person outside the RePEc team. The
| RePEc archive where the data is held in the form of ReDIF is on
| a disk to which a member of the RePEc team has write access.
| "archives of controlled sources"
| are archives for data from a single
| source that is provided by a person who belongs to the
| RePEc team.
| "dead archives" are archives that are no longer being maintained
| on the host where they lived originally and that have been moved to
| a site that is controlled by a member of the RePEc team.
|
| Table 1 lists the archives within these categories.
| Each archive is identified by a three-letter code. Some elementary metadata
| about the archive like its name, its url and some basic contents
| information are polled by a special central archive with the handle
| RePEc:all, where "RePEc" is the naming authority and "all" is the
| archive code.
|
|
|
|
|
| 4.1.1: Controlled collections
| The RePEc:wop archive contains the data from the WoPEc project. This
| project was opened by Thomas Krichel in April 1993 on a gopher server. At
| that time he placed the first electronic working paper in the
| discipline. During the following two years the emphasis of the archive
| shifted towards the description of remote documents, i.e. those which are
| not available on the local server. In 1998, as a result of a major
| collection and awareness raising effort undertaken by the WoPEc project in
| the United Kingdom the part of the RePEc:wop data that related to series in
| this country was taken out to form the RePEc:wuk archive. The maintenance
| of the series from outside the United Kingdom was contracted out to a team
| at the Siberian Branch of the Russian Academy of Sciences working under the
| leadership of Sergei Parinov.
| RePEc:wpa is the data from the Economics working paper archive at WUStL
| (EconWPA) as operated by Bob Parks. EconWPA
| opened in September 1993. It is a collection of electronic papers. It operates
| through author submissions in a much similar way as the
| xxx operates for Physics. Authors upload their papers
| with the archive and supply the bibliographic information themselves. In 1997 a
| converter was written by the Siberian team that converts these internal data to
| ReDIF.
| RePEc:hhs and RePEc:hhb archives maintained by the S-WoPEc and S-WoBa
| projects. These are Swedish national collections that gather data from many
| institutes. Section 4 of
| Karlsson and Krichel
| (1999) contains a
| comprehensive description of the way that these projects operate.
|
| 4.1.2: Hosted collections
| RePEc:fth is by far the largest archive. It describes
| over 28,000 papers but none
| of them are downloadable. It is a database produced by Fethy Mili, the
| Economics Departmental Librarian at Université de Montréal. He collects
| data on printed working papers that he receives. His collection is one of
| the largest on this planet. He receives about 300 series. In order to
| update the holdings in the archive he uploads an ASCII dump of its recent
| additions to the database. He then activates three scripts. These convert
| his data to ReDIF, add the new data to existing stock, remove
| duplications (that involves some manual work) and clean the file
| space. These scripts have been written by Thomas Krichel. He has direct
| access to Fethy Mili's files. They also collaborate to ensure that there
| are not many duplications between the data in RePEc:fth and the data
| provided in other archives. This effort requires the collaboration of the
| other archives as well. Clearly, data supplied directly by the provider of
| the papers is preferable to data supplied by an intermediary. However the
| data of the providers does not stretch as far back as Fethy's data. Ideally
| there should be a transfer of the data from the RePEc:fth archive to the
| archive of the original provider. The provider should then consolidate
| their data with the data from RePEc. There are cases where such a
| consolidation has been successful. However there are some cases where this
| consolidation is still forthcoming. In those cases there are double
| holdings of data.
| RePEc:fip contains the Federal Reserve of the United States' "Fed in
| Print" database. This database is a centrally collected database for all
| the documents that the Fed publishes. Every regional branch contributes
| data to the collections. These contribution sends a text dump via email to
| Thomas Krichel who then runs a converter into the ReDIF format. A similar
| process has been working since 1994, when the US Fed became the first
| governmental organization to contribute to the collection.
|
| 4.1.3: Controlled sources
| These are archives that make material available from a single
| provider. RePEc:nbr and RePEc:els are based on the machine of the
| provider. For others the providers use a variety of means to bring the
| data to a machine of the RePEc team member. RePEc:cpr use the most
| primitive way by physically delivering floppy disks to Thomas Krichel.
|
| 4.1.4: Dead archives
| RePEc:bru, RePEc:tex and RePEc:tcd are dead. These are archives that are no
| longer being maintained and are kept at a site under the control of a
| member of the RePEc team. It is not clear at what stage the archive is no
| longer being maintained. The best indication comes when an archive
| maintainer informs a member of the RePEc team that (s)he is leaving the
| workplace where (s)he built the archive. Another indication is that the
| archive can no longer be found at the url indicated in the archive
| template. (Note that it is possible to move an archive without
| notifying the keeper of the RePEc:all archive. To do that the old and new
| archives need to be held open simultaneously and the archive url must be
| set to the new archive on both locations until the RePEc:all archive has
| passed and taken a copy of the archive file with the new location.) Finally
| another indicator is when the archive has not been updated for a long
| time. There is currently no policy towards dead archives. It is likely that
| the number of dead archives will increase initially because the number of
| archives is increasing. Later the problem is likely to decline if
| participation in RePEc becomes a common practice.
|
| 4.2: Provider support
| The decentralized way of operating implies that any archive operator could
| write anything they like in the template. Racist, pornographic, arty-farty
| etc. expressions should be rare within the collection because each archive
| has to register with the keeper of the RePEc:all archive before the
| material from the archive can enter the RePEc distribution channels. All
| archives are based with recognized institutions or well-known
| academics. Any check on the semantics of the contents has to be performed
| by the archive maintainer herself. They should be quite competent at
| performing this task since it they posses the local knowledge that is
| required. However to encode that information into the templates some
| "remote" or "global" knowledge is required. We provide this
| knowledge in the documentation. We also aim to give the archive maintainers
| feedback on their data. This is what we deal with in this section. In
| particular we aim to provide the contributors with reports on the validity
| of their data.
| When we undertook this study we sent an email to all providers
| of loose archives. This email contained details about the checks. The
| checks were not publicized before in this way. They were included in the
| guide for archive maintainers that Christian Zimmermann maintains at
| http://ideas.uqam.ca/ideas/maintain.html. But it can be confidently
| assumed that when the data were collected the error files had not been
| used.
| Let arc be the three-letter code of an arbitrary archive. Then at
| ftp://netec.mcc.ac.uk/pub/RePEc/help/ arc.rech we
| store the result of a syntax check. It would be too long and too tedious to
| list the contents here. However we invite the reader to inspect those
| files. They are updated within a
| few hours of a change in the archive therefore the time stamp on the file
| will give a good indication for the time when the archive was last
| modified.
| The syntactic control is not the only one that we need to do. Since the
| templates are in fact within a relational framework we need to make sure
| that the relationships are valid. Even without the fully relational
| features that the dataset is aimed to eventually cover there are some
| relational features that need checking. For example, a paper handle
| RePEc:arc:xyzxyx:1999-1 would make no sense if there is no series
| RePEc:arc:xyzxyx defined in the dataset. If this is not the case it
| is likely that a user service on the web for example would have at least
| one broken link that would point from the paper to its series or
| vice-versa. Note that the relational control is computationally much more
| involved than the syntactical check. The syntax check only needs to look at
| an individual template. The relational check needs to be aware of the
| complete dataset. This has some important implications for the idea of a
| decentralized and relational database. The full extent of these
| implications has yet to be revealed. For the moment moment we provide a
| relational check at
| ftp://netec.mcc.ac.uk/pub/RePEc/help/ arc.rela .
| The last check is to control the url in the dataset. This is useful to find
| broken links to the full text of documents.
| A dataset as large as RePEc will never be completely error-free. There are
| many mistakes which are not machine-understandable and which therefore need
| human control. To deal with machine-understandable errors before they ever
| reach the user would be a desirable aim to reach. At the moment only the
| syntax check is performed at the time when the ReDIF data is read. Ideally
| one would like to see a check of the relational features as well as the
| control of the URLs be performed when the data is read. The only way that
| this could be done is to compute centrally a list of blacklisted templates.
| This is an area for future work.
| Finally there is an email discussion list for RePEc. It is called
| repec-admin. This is
| essentially meant for the common concerns of archive providers. There is
| not a lot of traffic on the list.
| Most discussion concern general policy issues such as
| copyright and data on usage. We estimate that only about one in three
| archives have a representative on the list.
|
| 4.3: The loose archives
| In order to gather some data about the loose archives we sent an email to
| all 66 loose archives. It was sent to the addresses that are listed in the
| Maintainer-Email field of the archive template. The mail informed about the
| maintainer support that we detail in the Subsection
| 4.2 (The text of the mail and the responses
| is available from the authors on request.) After sending a reminder, we
| achieved 22 responses. The small number of replies that we received is
| cause for concern. For anonymous questionnaires a response rate of one in
| three would be a great success. However we are dealing with a situation
| where the maintainer have some knowledge about what we are doing. There
| must be a common concern between us and the maintainer. Recall that almost
| all of them took the initiative to open the archive in the first place.
| The first question concerned the personal address of the
| respondent. In the second question we were interested in the professional
| status of the respondent How would you describe your function?
| ("academic faculty", "researcher", "computing officer",
| "publications officer", "secretary", "student" etc).
| Eleven respondents are academic staff, either in teaching or in
| full-time research positions, three professional researchers outside
| academia--we will group these as faculty respondents in the
| following--three students, two computer systems administrators, one
| librarian, one secretary, and one publications officer. The academic
| faculty were the first to respond, most of the answers we received from the
| others came after the reminder email.
| The next question concerned
|
| Briefly describe how your RePEc archive was initiated.
| For example: who had the idea, why did you open the archive...
|
| Here all the faculty respondents write that they opened the archives
| themselves. Eight of them mention that they have been approached by a
| member of the RePEc team. Six of them mention general awareness of RePEc.
| One student maintainer says that he was approached by the webmaster. All
| other non-faculty respondents report that they have been approached by
| faculty members.
| We already come up with one interpretation. It seems
| that the work on the archive works best when the academics are
| taking the initiative.
|
| Briefly describe how the archive is maintained.
| For example: who is involved in maintaining it, do you update the
| files regularly, how do you collect the data...
|
| The answers to this question are very difficult to summarize. Suffice is to
| say that we did not find two institutions that have the same
| procedures. Some involve as many as three persons in the process. Some use
| in-house scripts to update the server or to input the data. Even if
| academics are doing it on their own every single one of them seems to find
| a different way to do it. We conclude that trying to write a
| software that would help to automate the process would be very difficult
| because the software would have to cope with a large variety of individual
| organizational structures.
| Are the researchers aware that their work is disseminated though
| IDEAS/NEP/WoPEc etc?
| Here we have 16 answers that broadly say "yes" versus 6 that broadly say
| "no". A word of caution is on order here. An archive maintainer can
| easily state that the researchers are aware of it if she told them once
| that the research was disseminated. As one maintainer put it: "I keep
| reminding them but my guess is, less than 30% remember".
| Do you find it difficult/cumbersome to make the updates?
| What could we do to help you?
| All respondents write that it was easy or fairly easy to perform the
| updates. Many add that they did not need any further help. Suggestions are
| few and far between. None of them suggest procedural changes with the
| provision of the data. While this is a favorable result we must not forget
| that only one in three maintainers replied. It is possible that the other
| maintainers are rather confused and therefore did not bother to reply.
| We have some anecdotal evidence to support this idea.
|
| 5: The total dataset
|
|
| |
| |
| ReDIF-paper |
| ReDIF-article
|
| |
| |
| field |
| all |
| max |
| all |
| max
|
| |
| |
| template-type |
| 58254 |
| 1 |
| 10112 |
| 1
|
| |
| |
| handle |
| 58251 |
| 2 |
| 10110 |
| 1
|
| |
| |
| title |
| 58235 |
| 2 |
| 10110 |
| 1
|
| |
| |
| author-name |
| 98321 |
| 14 |
| 13855 |
| 6
|
| |
| |
| creation-date |
| 52730 |
| 1 |
| 8819 |
| 1
|
| |
| |
| revision-date |
| 536 |
| 8 |
| |
|
|
| |
| |
| publication-date |
| |
| |
| 510 |
| 1
|
| |
| |
| abstract |
| 22984 |
| 3 |
| 1896 |
| 1
|
| |
| |
| classification-jel |
| 20194 |
| 2 |
| 436 |
| 1
|
| |
| |
| keywords |
| 39219 |
| 3 |
| 9084 |
| 1
|
| |
| |
| keywords-attent |
| 457 |
| 1 |
| |
|
|
| |
| |
| publication-status |
| 6227 |
| 3 |
| 1568 |
| 1
|
| |
| |
| note |
| 9011 |
| 1 |
| 1479 |
| 2
|
| |
| |
| series |
| 4124 |
| 2 |
| |
|
|
| |
| |
| number |
| 16021 |
| 2 |
| 1501 |
| 1
|
| |
| |
| price |
| 4175 |
| 3 |
| |
|
|
| |
| |
| file-url |
| 17259 |
| 22 |
| 1853 |
| 2
|
| |
| |
| order-url |
| 2417 |
| 1 |
| |
|
|
| |
| |
| contact-email |
| 1141 |
| 1 |
| |
|
|
| |
| |
| availability |
| 7169 |
| 2 |
| |
|
|
| |
| |
| length |
| 33342 |
| 12 |
| |
|
|
| |
| |
| pages |
| |
| |
| 7920 |
| 1
|
| |
| |
| month |
| |
| |
| 489 |
| 1
|
| |
| |
| issue |
| |
| |
| 8705 |
| 1
|
| |
| |
| volume |
| |
| |
| 1293 |
| 1
|
| |
| |
| year |
| |
| |
| 1293 |
| 1
|
| |
| |
| journal |
| |
| |
| 488 |
| 1
|
| |
| |
| paper-handle |
| |
| |
| 19 |
| 1
|
| |
|
| |
|
|
|
| 5.1: Aggregate Contents
| In Table 2, we examine the document data in RePEc as of 1 May 1999. For
| each field we give the total occurrences of the field in the "all" column
| and the maximum of occurrences that the field has within a single template
| in the "max" column. The document data appear in the ReDIF-paper and the
| ReDIF-article templates.
|
| Total numbers for documents are given by the "template-type" and
| "handle" fields. Since each template should have exactly one type and
| exactly one handle the tiny difference between the two numbers is made up
| of mistakes in the dataset. The title field is also required. It is
| encouraging to see that most documents have a creation date attached to
| them,
| because as the dataset grows it will become increasingly important to
| distinguish between recent and dated documents; only the former are likely
| to be of much interest. By contrast "revision-date" information is rare.
| Articles may also have a "publication-date". The difference of this field
| with the "creation-date" field is not clear. We consider this to be a
| design error in the template structure.
|
| Let us consider the elements that refine the contents description. We
| encourage contributors to provide abstracts. The presence of abstracts for
| about one in three papers is very positive. The abstract field can be
| repeated. This is desirable when there are abstracts in different
| languages. A large number of the papers have a Journal of Economic
| Literature (JEL) classification code attached to
| them. However almost all papers in the offline papers only archive
| RePEc:fth have the codes and that explains a very large
| proportion of the
| classified material. This data has been compiled by a librarian.
| For the electronic papers there are only two in five papers that have a
| classification field. We agree that this is a serious limitation to the
| quality of the data. It would have been possible to require a
| classification number for each paper right from the start. This would have
| hampered the collection effort. In particular it would have made it
| impossible for the WoPEc team to "snarf" bibliographic data from sites
| where this JEL data was not available. There is also some concern among
| economists that their areas of work do not match with these codes. The use
| of more complete and sophisticated classification schemes would not be
| possible. The main argument against requiring JEL classification codes was,
| however, that there is considerable opposition against the scheme in the
| heterodox Econonomics commonity. They feel that the JEL classification
| scheme reflects the view of the orthodoxy. Requiring JEL classification
| codes would have meant excluding these contributors. Then and now only a tiny part of
| the collection could be grouped as heterodox. However our aim is that RePEc
| be a broad church. This was the decisive argument against requiring the use
| of JEL codes.
| There is a large number of templates that have keywords. About 50% of these
| templates come from RePEc:fip where each paper has a keyword. ReDIF allows
| for both free and qualified controlled vocabulary. This facility is
| used by for the internal keyword scheme of the Attent: Research
| Memoranda database. They
| are only used by the RePEc:dgr archive.
|
| The "publication-status" field can be used to indicate where the paper
| has been submitted to and where the paper has been formally published.
| This field appears in the data from large research bodies that have been
| issuing a series of papers for many years and that have data about the
| formal publication of the papers. The fields "series" and "number" are
| somewhat redundant since this information should also be available from the
| handle. The "price" field normally refers to the delivery of a printed
| copy. The mode of delivery is often just expressed in the "price" field.
| The "file-url" field refers to the "full text" locus of a part of the
| full text. Usually it is the complete full text.
| The document may have several
| components in addition to the full text. These can be listed as several
| "file" clusters. Each may carry an uncontrolled field about its function
| within the paper. For example the author may wish to supply a computer
| program that was used to produce the paper. In that case a whole series of
| files may be made available. However that is not the way the option of
| having many files is actually exercised. Most of the time it is used to
| include elements like graphics or tables that the author did not manage to
| include into the main document file.
| The "order-url" field is used to point to an intermediate page that sits
| between our description and the files of the document. In that case we are
| not aware if the resource does actually exist online. "order-url" may be
| used in conjunction with the "file-url" attribute. Note that there is no
| "order-email" field in the document templates. Such a field figures in
| the series template, because the ordering of a paper should be the same for
| all papers in the series. The "contact-email" may otherwise be used to
| contact somebody who has any connection with the paper. This field is
| only used by the contributors to the RePEc:wpa archive. The
| "availability" is used most of the time to signal that the paper is no
| longer in print.
| Finally a
| "length" attribute can be used to indicate how many pages the reader has
| to go through to read the paper. This field is present in all templates
| provided by RePEc:fth and it seems to appear in a surprisingly large number
| of other templates.
| Articles have a number of specific attributes that are listed at the bottom
| of the table. Strictly speaking these are not descriptive elements of the
| articles themselves, they rather relate to the position the article has
| within the journal. Finally the "paper-handle" allows to point from the
| preprint version to the article template.
|
|
| |
| file |
| person |
| organization
|
| |
| |
| name |
| all |
| max |
| | name |
| all |
| max |
| name |
| | all |
| max
|
|
| |
| |
| url |
| 19112 |
| 1 |
| | name |
| 112176 |
| 1 |
| | name |
| 8598 |
| 1
|
|
| |
| |
| format |
| 19024 |
| 1 |
| | postal |
| 8 |
| 1 |
| | postal |
| 2118 |
| 2
|
|
| |
| |
| size |
| 2630 |
| 1 |
| | homepage |
| 1557 |
| 2 |
| | homepage |
| 596 |
| 2
|
|
| |
| |
| function |
| 1661 |
| 1 |
| | email |
| 3166 |
| 2 |
| | email |
| 1451 |
| 3
|
|
| |
| |
| restriction |
| 2548 |
| 1 |
| | phone |
| 282 |
| 1 |
| | phone |
| 164 |
| 1
|
|
| |
| |
| |
| |
| |
| | fax |
| 259 |
| 1 |
| | fax |
| 197 |
| 1
|
|
| |
| |
| |
| |
| |
| | workplace-name |
| 8598 |
| 4 |
| | |
| |
|
|
|
| |
| |
|
|
| 5.2: The clustered data
| The data available in Table 2 is not the complete set of information
| available in the dataset. It only lists the individual attributes and the
| key attributes of clusters in the paper and article templates. In Table 3
| we have the data that is contained in the clusters in the document subset
| of the RePEc data. This data is therefore consistent with the data in Table
| 2.
| There are three types of clusters, "file", "organization" and
| "person". The numbers that are present suggest that there are significant
| possibilities for a relational structure in the dataset between persons and
| their organizations. An interesting consideration in the person cluster is
| the high number of workplace templates. Providers of the data seem to
| attribute more importance to the workplace of a person rather than to her
| strictly personal data, e.g. her homepage. The only explanation that we can
| offer here is that most likely the data is provided by an agent of the
| workplace. The low number of homepages is an indicator which also suggests
| that in most cases the provider is not the author herself. Note also that
| the workplace information--when it is present--is much more
| complete than the corresponding data for the individuals.
|
| 5.3: Mistakes in the data
| When a dataset is provided by various parties at the same time it is not a
| good idea to use the data directly. Recall that mirroring software is being
| used to keep updated copies of archives on sites that unite more than one
| archive. An archive could provide a site with an arbitrary stream of
| nonsense data. To avoid that data to appear in a user service we need to
| check the data at the time of reading. There are two types of problems
| that the software notices when it reads ReDIF templates: "errors" and
| "warnings". An "error" result in the template being discarded. A
| "warning" results in the value of the
| field being ignored. We deal with both
| problems later on. Note that the distinction between errors and
| warnings is not part of the published ReDIF documentation. It is specified
| in the specification file of the ReDIF checking software, see
| Krichel and Kurmanov
| (1999).
|
| 5.3.1: ReDIF Errors
| In Table 4 we show the errors that are in the data. At the start of the
| template, the first element has to be the template type. The border of the
| template is the zero-width space between the template-type statement and
| what precedes it. The checking software is able to signal the error that
| the template is not valid because it has as invalid start.
| Another type of error is the omission of a required field. The handle
| field is of course a mandatory field. For papers and articles we also
| require the name of at least one author, and the title. The requirement
| that leads to most errors is the specification of the file format. A
| document--whether a paper or an article--will be represented in
| a number of files. For each of those files we require a statement about
| the file format (say PDF, postscript etc) as well as some indication about
| the compression or archiving software that is being used.
| This requirement was inspired from our experience with user services.
| The early user services of RePEc were confronted
| with the problem to teach users what to do with the files when they had
| downloaded them. If the format of the file was documented it became
| possible to link each file to a documentation page that would explain users
| how to deal with the file. When such links were introduced at the WoPEc
| project in 1996 the number of queries fell dramatically.
| The need to require file formats was therefore introduced into the
| ReDIF specification.
| The next errors listed in Table 3 concern fields that repeated but that
| ReDIF does not allow to repeat. No template may have two handles and no
| document may have two titles.
|
|
|
| |
| description of error |
| | number
|
| |
| |
| Start template with 'template-type' attribute |
| | 122
|
| |
| |
| Required attribute <handle> is absent |
| 6
|
| |
| |
| Required attribute <title> is absent |
| 23
|
| |
| |
| Required attribute <author-name> is absent |
| | 8
|
| |
| |
| Required attribute <format> is absent in <file> |
| | 264
|
| |
| |
| You cannot repeat (2) this attr <handle> in templ above |
| | 1
|
| |
| |
| You cannot repeat (2) this attr <title> in templ above |
| | 1
|
| |
| |
| Attribute misplaced; valid in cluster <file> |
| 104
|
| |
| |
| Attribute misplaced; valid in cluster <organization> |
| | 32
|
| |
| |
| Attribute misplaced; valid in cluster <person> |
| | 2
|
| |
| |
| Attribute misplaced; valid in template <redif-archive 1.0> |
| | 14
|
| |
| |
| Attribute misplaced; valid in template <redif-person 1.0> |
| 4
|
| |
| |
| INVALID (unknown) attribute |
| 126
|
| |
| |
| Invalid value of type <email> (attr: contact-email, eval) |
| 1
|
| |
| |
| Invalid value of type <fileformat> (attr: file-format, regex) |
| 112
|
| |
| |
| Invalid value of type <handle> (attr: handle, regex) |
| 10
|
| |
| |
| Invalid value of type <url> (attr: author-homepage, eval) |
| 82
|
| |
| |
| Invalid value of type <url> (attr: file-url, eval) |
| 77
|
| |
| |
| Bad line: |
| 1189
|
| |
|
| |
|
|
| An important source of mistakes is the clustering of attributes. A cluster
| must be introduced with the key attribute for the cluster; if that is not
| the case then the template is in error. However given the fact that the
| cluster concept is more involved than than the meaning of individual
| data element we are surprised that there are not more clustering mistakes.
| Each attribute may be checked for its syntax to correspond to a regular
| expression. Email addresses have to be of the standard Internet form
| user@site. URLs have to be of a syntax that is specified in
| RFC1783. The format
| indicator that is required in the file-format is an in-house product. It is
| based on the mime types as defined in
| RFC1521 but it has
| additional qualifiers that specify archiving and compression of files. It
| is therefore not astonishing that this specification produces quite a few
| mistakes.
| Finally an important source of mistakes are bad lines. This error typically
| occurs in lines that continue the value of a field that has started on a
| previous line. Any such line must be indented by at least one blank
| character. Note that the number quoted here is the actual number of bad
| lines. If an abstract that goes over several lines has no indentation, this
| problem affects all the lines. The number of templates that are affected
| by the problem is therefore much smaller than the number reported
| here. Our calculations show that 170 templates are invalid through
| bad lines. Note that the same remark also applies for the
| "missing template-type" error.
|
| 5.3.2: ReDIF warnings
| When a warning is issued, the template is not rejected but the value of the
| field is ignored. We list the warning messages in Table 4.
| Dates have to be of the form yyyy-mm-dd. The JEL
| classification values are all known to the checking software. If a key
| attribute is empty then the rest of the cluster data is ignored.
|
| 5.3.3: Guildford protocol mistakes
| When preparing this paper we also found some violations of the Guildford
| protocol. Recall that the Guildford protocol sets rules on how ReDIF
| metadata should be stored on a RePEc archive. (When ReDIF is
| checked these errors are not detected because they are not violations of
| ReDIF.) Three files contained series templates but they are not called
| ???seri.rdf and placed in the directory of individual series. There is
| also a file that contains a mixture of ReDIF-paper and ReDIF-software
| templates. This is not licit because no file may contain templates of
| different types.
| Since we have been working very thoroughly through the
| data we are confident that there are no further Guildford protocol mistakes
| in the data. To prove that we would need to write special software.
|
| 5.4: The composition of the dataset into archives
| In Tables 5 and 6 (in the Appendix) we report the contents of the total
| document-related datasets for loose and controlled archives respectively.
| For each archive, we give its name first; two names have been shortened in
| order to save space. It is clear that the name of the archive is not really
| a well defined concept. For most loose archives the choice of the name
| reflects the name of the provider or sometimes simply the name of the type
| of papers.
| The largest archives tend to be found among the controlled archives. The
| reasons are simple enough. Many of the controlled archives come from large
| providers. A member of the RePEc team has been working to make their
| contents available, because the bargaining power of large providers is such
| that they have little incentive to provide data but RePEc has strong
| incentives to include them. The majority of loose archives are run by small
| institutions, in general for their departmental paper series. There are
| some personal archives; we will look at them separately.
|
|
|
| |
| description of error |
| number
|
| |
| |
| A bad date value format: |
| 273
|
| |
| |
| An invalid JEL value |
| 3344
|
| |
| |
| Empty value of a key attr. <author-name> |
| 301
|
| |
| |
| Empty value of a key attr. <author-workplace-name> |
| 1411
|
| |
| |
| Empty value of a key attr. <file-url> |
| 176
|
| |
|
| |
|
|
|
| 5.4.1: Controlled versus loose archives
| There are two basic reasons why mistakes occur in an archive. Either the
| maintainer is incompetent or (s)he is lazy. In the case of the controlled
| archives we exclude the incompetence cause. We assume that these people are
| competent but that they have not yet corrected the mistakes because they
| have been too lazy, too busy with other things or for whatever other
| reasons. The main issue for us is whether people who have neither formal
| cataloging background in general nor have had
| personal training in particular are
| able to catalog the documents. If they can do that as well as people who
| have perfect knowledge of the cataloging procedure than it is possible to
| build a catalog simply by pointing a willing individual to the
| documentation.
| It is therefore important to consider the comparative number of mistakes in
| these two groups of archives. Because of the fact that the controlled
| archives are so much larger a comparison of the quality of the controlled
| versus the loose archive would be misleading if it would solely based on
| statistical measures like the total number of errors divided by the total
| number or documents. Since the large collections are generated out of ASCII
| dumps from bibliographic databases, this comparison would be misleading.
| From an examination of the data in Table 5, there seems to be an
| accumulation of mistakes in certain archives whereas others are almost
| completely error-free. Even some of the controlled archives are affected by
| a series of problems. It therefore seems fair to write that in principle
| the decentralized cataloging works for a large number of archives. However
| a small number are affected by clusters of mistakes. There is some human
| intervention required to fix these mistakes. Note that because web
| cataloging is still in its infancy, we can be hopeful that sooner or later
| the archives that are affected by serial errors will take corrective
| action.
|
| 5.4.2: Personal archives
| Four archives are in fact personal archives where paper of only one person
| and his co-authors appear. Three of them take their name
| from the person who
| is the main author. RePEc is ill-prepared for the wide-spread use idea of a
| personal RePEc archive. Since all archives have to be registered with a
| central archive, if many of authors open such archives this would put the
| central archive under considerable strain. The three archives are operated
| by leading gurus and therefore the RePEc team did find it difficult to
| refuse them to open an archive. If authors would make more material
| available in homepages, one would need to find intermediate collectors
| that would gather the ReDIF data not through the Guildford protocol, but
| through a protocol that is more suitable for the storage of ReDIF data
| in homepages.
| One important motivation to store papers in personal archives is that many
| journals allow authors to redistribute their work as part of a collection
| that is their own. Providers of personal archives provide reprints of
| their paper and hope that these reprints are protected by such clauses.
|
| 6: Conclusions
| The free provision of educational material can be implemented through a
| central institution. Such an institution needs to be subsidized by central
| funds. The alternative is to provide the resources by a large number of
| agents. Then the cost of providing access can be absorbed within each
| institution. In that case the question of a comprehensive catalog
| arises. Such a catalog is needed to provide access to the collection in a
| unified way.
| In this paper we have dealt with the provision of a key resource
| i.e. academic papers. We have presented a collection of metadata that is
| provided by decentralized archives. We have found that it is possible to
| build such a collection to a reasonable degree of accuracy if some archives
| where mistakes occur are aided by others. There needs to be a small group
| of people who actively support the collection. However this support can be
| given in decentralized fashion without the need for much coordination
| between supporters.
| The academic library commonity in the United Kingdom as a whole has made a
| important contribution to RePEc by donating funds to the work of the WoPEc
| project. This has allowed the WoPEc project to collect metadata about
| papers that are published by institutions that are not yet contributing to
| RePEc. This was a vital aspect of WoPEc project. The data collected by
| WoPEc constituted 90% of the RePEc data when RePEc was founded. However
| nowadays that proportion is falling. The funding for WoPEc has run out but
| the WoPEc web site continues to expand because of the contributions by made
| by RePEc archives. The software is maintained by volunteers.
| Librarians should carefully consider the vision of the project. This is a
| kind of academic self-organization where academics publish and catalog
| their own work. RePEc benefits from network externalities. The more
| academics join the more those who have not joined will feel pressure to
| join. If the data is freely available than authors can commonicate with
| their peers without the need of intermediaries. The providers of
| intermediation services have every reason to be worried. They include
| publishers and librarians. If librarians do not play
| a more active part by supporting developments like RePEc there will be no
| more rôle for them in the future.
|
|
| <hr>
| The work
| discussed here has received financial support by the Joint
| Information Systems Committee of the UK Higher Education Funding
| Councils through its
| Electronic Library Programme.
| We are grateful to
| Christopher F. Baum,
| Robert P. Parks,
| Thorsten Wichmann and
| Christian Zimmermann
| for comments on the questionnaires.
| William L. Goffe and
| Christian Zimmermann
| made many helpful suggestions.
| Sophie C. Rigny kindly pointed
| out many stylistic and grammatical errors in an earlier version.
|
Appendix:
| The composition of the dataset by archive
|
|
|
|
|
|
|
|
| |
| School of Economics and Management, University of Aarhus, Denmark
|
| |
| |
| RePEc:aah |
| 2 |
| series |
| 200 |
| papers |
| 0 |
| articles |
| 162 |
| errors |
| 5 |
| warnings
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| Ecological Economics Program RePEc Archive
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| |
| RePEc:anu |
| 1 |
| series |
| 14 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
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| Bank of Canada
|
| |
| |
| RePEc:bca |
| 2 |
| series |
| 47 |
| papers |
| 0 |
| articles |
| 0 |
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| 0 |
| warnings
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| Brazilian Electronic Journal of Economics
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| RePEc:bej |
| 2 |
| series |
| 0 |
| papers |
| 3 |
| articles |
| 20 |
| errors |
| 0 |
| warnings
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| RePEc archive at Berlecon Research
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| |
| RePEc:ber |
| 1 |
| series |
| 4 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
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| Working Papers Archive of the Bank of England
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| |
| RePEc:boe |
| 1 |
| series |
| 94 |
| papers |
| 0 |
| articles |
| 25 |
| errors |
| 0 |
| warnings
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| RePEc archive at Bonn University
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| |
| |
| RePEc:bon |
| 2 |
| series |
| 682 |
| papers |
| 0 |
| articles |
| 86 |
| errors |
| 348 |
| warnings
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| Brown University, Department of Economics
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| RePEc:bro |
| 1 |
| series |
| 56 |
| papers |
| 0 |
| articles |
| 1 |
| error |
| 14 |
| warnings
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| Banking & Finance Conference Papers
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| RePEc:caf |
| 1 |
| series |
| 6 |
| papers |
| 0 |
| articles |
| 1 |
| error |
| 0 |
| warnings
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| Department of Applied Economics Working Paper Archive
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| |
| RePEc:cam |
| 3 |
| series |
| 81 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
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| Concordia University, Department of Economics
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| RePEc:ccd |
| 1 |
| series |
| 2 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
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| Centre for Economic Performance, London School of Economics
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| |
| RePEc:cep |
| 3 |
| series |
| 362 |
| papers |
| 0 |
| articles |
| 57 |
| errors |
| 613 |
| warnings
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| CEPII
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| |
| RePEc:cii |
| 1 |
| series |
| 81 |
| papers |
| 0 |
| articles |
| 42 |
| errors |
| 0 |
| warnings
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| |
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| Canadian Journal of Economics
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| |
| RePEc:cje |
| 1 |
| series |
| 0 |
| papers |
| 76 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
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| Levine's Working Paper Archive
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| |
| |
| RePEc:cla |
| 1 |
| series |
| 43 |
| papers |
| 0 |
| articles |
| 1 |
| error |
| 0 |
| warnings
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| CEPREMAP Archive
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| |
| |
| RePEc:cpm |
| 1 |
| series |
| 770 |
| papers |
| 0 |
| articles |
| 1 |
| error |
| 7 |
| warnings
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| |
| |
| Department of Economics Discussion Papers Archive at City University
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| |
| |
| RePEc:cty |
| 1 |
| series |
| 34 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
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| |
| |
| Working Papers of the Department of Economics at Dalhousie University
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| |
| |
| RePEc:dal |
| 1 |
| series |
| 0 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
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| |
| |
| DEGREE
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| |
| |
| RePEc:dgr |
| 18 |
| series |
| 1203 |
| papers |
| 0 |
| articles |
| 663 |
| errors |
| 292 |
| warnings
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| |
| |
| Archive for RePEc at UPV-EHU
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| |
| |
| RePEc:ehu |
| 1 |
| series |
| 7 |
| papers |
| 0 |
| articles |
| 2 |
| errors |
| 1 |
| warning
|
| |
| |
| Fondazione Eni Enrico Mattei
|
| |
| |
| RePEc:fem |
| 1 |
| series |
| 54 |
| papers |
| 0 |
| articles |
| 371 |
| errors |
| 0 |
| warnings
|
| |
| |
| Financial markets Group, London School of Economics
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| |
| |
| RePEc:fmg |
| 3 |
| series |
| 429 |
| papers |
| 0 |
| articles |
| 75 |
| errors |
| 449 |
| warnings
|
| |
| |
| Universitaet Frankfurt, Wirtschaftswissenschaften
|
| |
| |
| RePEc:fra |
| 1 |
| series |
| 31 |
| papers |
| 0 |
| articles |
| 5 |
| errors |
| 0 |
| warnings
|
| |
| |
| Economics Working Paper Archive at the University of Glasgow
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| |
| |
| RePEc:gla |
| 1 |
| series |
| 54 |
| papers |
| 0 |
| articles |
| 30 |
| errors |
| 0 |
| warnings
|
| |
| |
| Heriot Watt University, Edinburgh
|
| |
| |
| RePEc:hwe |
| 2 |
| series |
| 62 |
| papers |
| 0 |
| articles |
| 1 |
| error |
| 0 |
| warnings
|
| |
| |
| IGIER-Innocenzo Gasparini Institute for Economic Research
|
| |
| |
| RePEc:igi |
| 1 |
| series |
| 58 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Economic Working Paper Archive at University of Jena
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| |
| |
| RePEc:jen |
| 2 |
| series |
| 56 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 1 |
| warning
|
| |
| |
| CoFE Discussion Paper
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| |
| |
| RePEc:knz |
| 1 |
| series |
| 6 |
| papers |
| 0 |
| articles |
| 78 |
| errors |
| 1 |
| warning
|
| |
| |
| University of Leicester Disccussion Papers in Economics
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| |
| |
| RePEc:lec |
| 3 |
| series |
| 89 |
| papers |
| 0 |
| articles |
| 2 |
| errors |
| 0 |
| warnings
|
| |
| |
| Lester Ingber Papers Archive
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| |
| |
| RePEc:lei |
| 1 |
| series |
| 50 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Universite Laval, Departement d'economique
|
| |
| |
| RePEc:lvl |
| 2 |
| series |
| 152 |
| papers |
| 0 |
| articles |
| 1 |
| error |
| 1 |
| warning
|
| |
| |
| Economics Working Paper Archive NUIM
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| |
| |
| RePEc:may |
| 1 |
| series |
| 31 |
| papers |
| 0 |
| articles |
| 5 |
| errors |
| 0 |
| warnings
|
| |
| |
| Non-monetary economics
|
| |
| |
| RePEc:mce |
| 1 |
| series |
| 2 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Economics Working Paper Archive at McGill
|
| |
| |
| RePEc:mcl |
| 1 |
| series |
| 7 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| McMaster University Department of Economics Working Paper Series
|
| |
| |
| RePEc:mcm |
| 5 |
| series |
| 274 |
| papers |
| 0 |
| articles |
| 4 |
| errors |
| 1 |
| warning
|
| |
| |
| Economics Working Paper Archive at Universidad Publica de Navarra (UPNA)
|
| |
| |
| RePEc:nav |
| 1 |
| series |
| 1 |
| paper |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Economics works by Nir Dagan and Oscar Volij
|
| |
| |
| RePEc:nid |
| 2 |
| series |
| 25 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Netnomics
|
| |
| |
| RePEc:nnm |
| 0 |
| series |
| 0 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Economics Discussion Papers Archive at Nottingham
|
| |
| |
| RePEc:not |
| 2 |
| series |
| 110 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| National Institute of Economic and Social Research
|
| |
| |
| RePEc:nsr |
| 1 |
| series |
| 126 |
| papers |
| 0 |
| articles |
| 7 |
| errors |
| 0 |
| warnings
|
| |
| |
| SUNY-Oswego Economics Department Working Paper Archive
|
| |
| |
| RePEc:nyo |
| 1 |
| series |
| 5 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Ohio State University, Department of Economics
|
| |
| |
| RePEc:osu |
| 1 |
| series |
| 18 |
| papers |
| 0 |
| articles |
| 1 |
| error |
| 0 |
| warnings
|
| |
| |
| Working Papers and Published Papers by Peter Cramton and Co-Authors
|
| |
| |
| RePEc:pcc |
| 1 |
| series |
| 38 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Queen Elizabeth House Papers Archive at Oxford University
|
| |
| |
| RePEc:qeh |
| 1 |
| series |
| 21 |
| papers |
| 0 |
| articles |
| 5 |
| errors |
| 0 |
| warnings
|
| |
| |
| Centre for International Business Centre
|
| |
| |
| RePEc:sbu |
| 3 |
| series |
| 4 |
| papers |
| 0 |
| articles |
| 2 |
| errors |
| 11 |
| warnings
|
| |
| |
| CSEF-Centre for Studies in Economics and Finance Working Papers
|
| |
| |
| RePEc:sef |
| 1 |
| series |
| 20 |
| papers |
| 0 |
| articles |
| 1 |
| error |
| 9 |
| warnings
|
| |
| |
| University of Liège (Belgium) Faculty of Econonomics, Management and Social SciencesDepartment of Economics Service of International and Interregional Economics (SEII)
|
| |
| |
| RePEc:sei |
| 1 |
| series |
| 7 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Economics Discussion Paper Archive at the University of Siegen, Germany
|
| |
| |
| RePEc:sie |
| 1 |
| series |
| 19 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Economics Working Paper Archive at the University of Sussex
|
| |
| |
| RePEc:sus |
| 1 |
| series |
| 51 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| University of Toronto, Department of Economics
|
| |
| |
| RePEc:tor |
| 1 |
| series |
| 91 |
| papers |
| 0 |
| articles |
| 2 |
| errors |
| 0 |
| warnings
|
| |
| |
| Economic Working Paper Archive at UPO
|
| |
| |
| RePEc:uca |
| 1 |
| series |
| 2 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Department of Economics, University of Iowa
|
| |
| |
| RePEc:uia |
| 1 |
| series |
| 135 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Department of Economics Discussion Papers Archive at the University of Kent
|
| |
| |
| RePEc:ukc |
| 1 |
| series |
| 58 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Electronic Working Papers, Department of Economics, University of Maryland
|
| |
| |
| RePEc:umd |
| 1 |
| series |
| 11 |
| papers |
| 0 |
| articles |
| 34 |
| errors |
| 3 |
| warnings
|
| |
| |
| Economics Working Paper Archive at Universitat Pompeu Fabra
|
| |
| |
| RePEc:upf |
| 3 |
| series |
| 227 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
| |
| Department of Economics, University of Victoria
|
| |
| |
| RePEc:vic |
| 2 |
| series |
| 16 |
| papers |
| 0 |
| articles |
| 2 |
| errors |
| 0 |
| warnings
|
| |
| |
| Centre for the Study of Globalisation and Regionalisation (CSGR)
|
| |
| |
| RePEc:wck |
| 2 |
| series |
| 51 |
| papers |
| 0 |
| articles |
| 78 |
| errors |
| 0 |
| warnings
|
| |
| |
| SFB504 Working Paper Archive
|
| |
| |
| RePEc:xrs |
| 1 |
| series |
| 110 |
| papers |
| 0 |
| articles |
| 6 |
| errors |
| 3 |
| warnings
|
| |
| |
| Economics Working Paper Archive at York
|
| |
| |
| RePEc:yor |
| 1 |
| series |
| 190 |
| papers |
| 0 |
| articles |
| 0 |
| errors |
| 0 |
| warnings
|
| |
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