Quality assessment of a current awareness system

1
Quality assessment of a current awareness system

• Thomas Krichel
• LIU H??
• 20071023

2
acknowledgments

• Thanks to organizers.
• I am grateful for comment by
• Bernado Bátiz-Lazo
• Joanna P. Davies
• Marco Novarese
• Christian Zimmermann
• I thank everybody involved in RePEc and NEP, as
  well as JISC.

3
current awareness

• Current Awareness aka Selective Dissemination of
  Information is a simple idea a user is informed
  about new documents in her area of interest.
• Current awareness generate a double
  classification in
• subject ...
• time ...
• matter.

4
why bother?

• It is niche activity that has been neglected by
  the search engines.
• I have registered with Google and Amazon. They
  give me tips but these are generally poor.
• We can not trust computers to do it.
• Neither on subject matter
• Nor on time

5
types of current awareness

• personal (amazon) vs collective (Google news)?
• machine generated vs human generated?
• Actually I claim the only human-generated current
  awareness service for academic documents is NEP.

6
computer-based keywords

• In computer generated current awareness one can
  filter for keywords.
• In academic digital libraries, since the papers
  describe research results, they contain all
  ideas that have not been previously seen.
• Therefore getting the keywords right is
  impossible.

7
computer-based categories

• It is possible to classify documents based on
  categories say football vs tennis.
• It works fine when the vocabulary used in
  different categories is quite different.
• For some academic areas the differences are just
  too subtle.

8
computers and time problem

• In a digital library the date of a document can
  mean anything.
• The metadata may be dated in some implicit form.
• Recently arrived records can be calculated.
• But record handles may be unstable.
• Recently arrived records do not automatically
  mean new documents.

9
we need humans

• Catalogers are expensive.
• We need volunteers to do the work.
• Junior researchers have good incentives. They
• need to be aware of latest literature
• are absent from the informal circulation channels
  of top level academics
• need to get their name around among researchers
  in the field..

10
introducing NEP

• There is only one large freely-available
  human-based current awareness service.
• It is NEP New Economics Papers at
  http//nep.repec.org
• Remainder of this talk is about NEP.

11
NEP New Economics Papers

• NEP is a current awareness system for the working
  paper in the RePEc digital library about
  economics.
• Published articles are excluded because they are
  way too old.

12
NEP service model

• There is a basic model behind this service we
  could call the "NEP Service Model".
• two stages...
• flat report space...

13
general two stage setup

• First stage A general editor compiles a list of
  all new papers. This forms an issues of the
  allport.
• Second stage A group of subject editors filter
  the new allport issue into subject reports. Each
  editor does this independently for the subject
  reports she looks after.

14
a flat space

• There is a series of reports. Each reports has a
  number of issues over time.
• There is an allport a report that contains all
  papers that are new in the period covered by the
  issue.

15
first stage in NEP

• General editor compiles a list of recent
  additions to the RePEc working papers data.
• Computer generated
• Journal articles are excluded
• Examined by the General Editor (GE, a person)?
• This list forms an issue of nep-all.

16
first stage in NEP

• nep-all contains all new papers
• Circulated to
• nep-all subscribers
• Editors of subject-reports

17
second stage

• Each editor creates, independently, a subject
  report for her subject. She does this by removing
  from nep-all.
• A subject report issues (sri) is the result of
  this process.
• There have been over 47,000 sris issued through
  the lifetime of NEP to date.

18
history

• There are basically two phases in NEP the
  pre-ernad 1998 to 2004 and the post ernad phase.
• I will deal with pre-ernad history here.
• Some research on NEP has been conducted in the
  pre-ernad phase.
• This has informed the work that went into ernad.

19
early history

• System was conceived by Thomas Krichel
• Name NEP by Sune Karlsson
• Implemented by José Manuel Barrueco Cruz.
• Started to run in May 1998.

20
starting setup

• First the system was all email based.
• The nep-all was composed as an email.
• It was sent to editors as an email.
• Editors used whatever tool they used to compose
  the email.

21
web interface

• John S. Irons issued the first web interface for
  report composition on 2000-02-01.
• This would just compose the report.
• Editors would still cut and paste the results of
  the form into email clients.

22
historic mail support

• First mail support was given by mailbase.ac.uk.
• When this was closed in 2000-11, NEP moved to
  jiscmail.ac.uk.
• Since the mailing list service was only supposed
  to be for UK academic community, it was deemed
  not sustainable.
• Thomas Krichel started hosting lists on
  2002-11-16. It is a nightmare.

23
Aeroflot document

• The Aeroflot document was a thinking piece that
  Thomas Krichel wrote as early as 2001.
  http//openlib.org/home/krichel/work/aeroflot.html
  
• This paper already sets out ideas for what would
  be ernad.
• At that time the Siberian RePEc team promised
  help with building such a system.

24
discover disaster

• In 2002-2003 Jeremiah Cochise Trinidad
  Christensen and Thomas Krichel were the first
  people to try to get a systematic picture of how
  NEP works.
• They discover that this is exceedingly difficult.

25
mail log parsing

• Logs were not moved from to Maibase to JISCMail.
• Mailbase removed the logs in 2002-11. Thomas
  Krichel got them just before they were destroyed.
• The mail logs were the only source for historic
  NEP information.

26
parsing targets

• handles severely compromised by cut-n-paste
  operations, editor locales, etc.
• date of issue editors were free to set dates,
  nep-all dates may not be preserved
• time of issue an email is almost impossible to
  time.

27
state of pre-ernad data

• After a regular expressions orgy, we can get some
  approximate idea about the handles that were
  used.
• Thus the thematic component is roughly intact.
• We have a problem with a bug in the discovery
  program that made many papers appear several
  times in nep-all. This makes it difficult to
  associate subject and allport issues.

28
state of pre-ernad data

• Timing of emails is extremely difficult, even
  with full headers.
• The logs of the Mailbase system only have times
  for when the email client said it sent the mail.
  This is the local editor's PC time, can be years
  out of whack!
• We still have some data for research...

29
research conducted on NEP

• Most of the research conducted on ernad has been
  done in the pre-ernad phase.
• The difficulties of some of this work has
  informed the construction of ernad.

30
Chu and Krichel (2003)?

• Heting Chu Thomas Krichel (2003) NEP Current
  awareness service of the RePEc digital library.
  http//www.dlib.org/dlib/december03/chu/12chu.html
  vaguely talks about NEP. Notes that there is a
  problem of timeliness in the subject report
  issue, despite the very shaky data.

31
Barrueco Cruz et al. (2003)?

• Jose Manuel Barrueco Cruz, Thomas Krichel and
  Jeremiah Cochise Trinidad-Chrisitensen
  Organizing Current Awareness in a Large Digital
  Library http//openlib.org/home/krichel/papers/es
  poo.pdf have two themes
• overlap between reports...
• coverage ratio...
• as well as history and suggestions.

32
overlap

• Barrueco Cruz et al (2003) argue that overlap
  occurs not when two papers are appearing in the
  two reports, but when the two reports are read by
  the same readers.
• They have data on pairwise overlap between
  reports, based on crude membership data.

33
overlap puzzle

• Here is a puzzle to think about
• If a person will be interested in two subject
  areas because they are close, she will subscribe
  to both reports.
• But since they are thematically close, she will
  sometimes receive the same papers twice.
• With mail technology and asyn-chronous issue
  generation, this appears difficult to solve.

34
coverage ratio

• We call the coverage ratio the number of papers
  in nep-all that have been announced in at least
  one subject report.
• We can define this ratio
• for each nep-all issue
• for a subset of nep-all issues
• for NEP as a whole

35
coverage ratio theory evidence

• Over time more and more NEP reports have been
  added. As this happens, we expect the coverage
  ratio to increase.
• However, the evidence, from research by Barrueco
  Cruz, Krichel and Trinidad is
• The coverage ratio of different nep-all issues
  varies a great deal.
• Overall, it remains at around 70.
• We need some theory as to why.

36
Krichel Bakkalbasi (2005)?

• Thomas Krichel and Nisa Bakkalbasi Developing a
  predicitve model of editor selectivity in a
  current awareness service of a large digital
  library. http//openlib.org/home/krichel/papers/b
  oston.pdf

37
coverage ratio theories

• Krichel Bakkalbasi (2005) build two theories of
  the observations of Barrueco Cruz at al. (2003)?
• They are
• Target-size theory
• Quality theory
• descriptive quality
• substantive quality

38
theory 1 target size theory

• When editors compose a report issue, they have a
  size of the issue in mind.
• If the nep-all issue is large, editors will take
  a narrow interpretation of the report subject.
• If the nep-all ratio is small, editors will take
  a wide interpretation of the report subject.

39
target size theory static coverage

• There are two things going on
• The opening new subject reports improves the
  coverage ratio.
• The expansion of RePEc implies that the size of
  nep-all, though varying in the short-run, grows
  in the long run. Target size theory implies that
  the coverage ratio deteriorates.
• The static coverage ratio is the result of both
  effects canceling out.

40
theory 2 quality theory

• George W. Bush version of quality theory
• Some papers are rubbish. They will not get
  announced.
• The amount of rubbish in RePEc remains constant.
• This implies constant coverage.
• Reality is slightly more subtle.

41
2 versions of quality theory

• Descriptive quality theory papers that are badly
  described
• misleading titles
• no abstract
• languages other than English
• Substantive quality theory papers that are well
  described, but not good
• from unknown authors
• issued by institutions with unenviable research
  reputation

42
practical importance

• We do care whether one or the other theory is
  true.
• Target size theory implies that NEP should open
  more reports to achieve perfect coverage.
• Quality theory suggests that opening more report
  will have little to no impact on coverage.
• Since operating more reports is costly, there
  should be an optimal number of reports.

43
results

• Krichel Bakkalbasi (2005) build a binary
  logistic regression analysis model.
• They find positive evidence for both target size
  and quality theory.
• The NEP editors don't like the results. They
  insist that they only filter by topic.

44
Bátiz-Lazo Krichel (2005)?

• Bernardo Bátiz-Lazo On-line distribution of
  working papers through NEP A Brief Business
  History http//openlib.org/home/krichel/papers/ka
  ssel.pdf has an early history of NEP that covers
  organizational details I don't talk about here.

45
ernad

• stands for editing reports on new academic
  documents.
• Software system designed by Thomas Krichel at
  http//openlib.org/home/kric hel/work/altai.html.
• Software written in Perl by Roman D. Shapiro.
  Cost 2000.
• Started to work after 2004-12.

46
cut editor freedom I

• Editors no longer send mail to lists.
• Only one email address sends mail.
• But the mail appears like coming from the editor
• From Marcus Desjardin lternad_at_nep.repec.orggt
• Reply-To Marcus Desjardin ltdesjardin_at_econ.louvain
  .begt

47
cut editor freedom II

• Editors can no longer edit report issue emails,
  e.g. add announcements of conferences.
• They are generated from XML files into
  standardized text and HTML files bound together
  by MIME multipart/alternative.
• They can not change dates of issue.

48
help editors

• Provide a simple-to-use interface for the
  composition of reports
• provide an easy to scroll input
• allow for easy sorting of report
• do a better job at pretty-printing
• Get ready for the introduction of pre-sorting
• Actually presorting was only introduced in
  2005-08.

49
statistical learning

• The idea is that a computer may be able to make
  decision on the current nep-all reports based on
  the observation of earlier editorial decisions.
  This is known as pre-sorting.
• Thomas Krichel Information retrieval performance
  measures for a current awareness report
  composition aid http//openlib.org/home/krichel/s
  endai.pdf deals with the evaluation of presorting.

50
presorting

• When an allport issue is created, it is
  presorted.
• In the allport rif each paper has a number in
  document order. That number is still reported in
  the presorted rif.
• The method is support vector machines svm, using
  svm_light.

51
pre-sorting reconceived

• We should not think of pre-sorting via SVM as
  something to replace the editor.
• We should not think about it encouraging editors
  to be lazy.
• Instead, we should think it as an invitation to
  examine some papers more closely than others.

52
headline vs. bottomline data

• The editors really have a three stage process of
  decision.
• They read title, author names.
• They read the abstract.
• They read the full text.
• A lot of papers fail at the first hurdle.
• SVM can read the abstract and prioritize papers
  for abstract reading.
• Editors are happy with the presorting system.

53
what is the value of an editor?

• It turns out that reports have very different
  forecastability. Some are almost perfect, others
  are weak.
• If the forecast is very weak the editor may be
• a genius
• a prankster.

54
svm training set

• The positive examples are taking from the report
  up to a certain time limit, called the experience
  length.
• The negative results are taken from nep-all, from
  the date of the last issued subject report until
  the experience length.
• The experience length is fixed in ernad.conf. For
  NEP it is 13 months.

55
features selection

• We use individual words out of the contents from
  titles, author names, abstracts, classification
  data and the id of the RePEc series.
• We normalize the Euclidean sum of the feature
  weights.
• We run svm_light with the default settings.

56
presorting timeline

• When a nep-all issues has been created, a
  customized version of its rif is created in the
  source/us directory.
• This issue is then presorted. The presorted
  version is stored in the source/ps directory.
• Presorting therefore only takes account of the
  information available at nep-all creation time.

57
underlying technologies

• Written in Perl, using LibXSLT.
• Uses mod_perl under Apache 2.
• Runs on Debian GNU/Linux, could run on similar
  systems.
• Ernad needs to used some sort of mailing system
  but is not geared to a specific system. It
  basically just sends mail.

58
underlying information

• AMF is a format for description of academic
  documents and academics.
• http//amf.openlib.org/doc/amf.html
• It is based on XML Schema, itself based on XML.
• Report data and issue data is encoded in AMF.

59
ernad.conf

• Ernad uses one single configuration file
  ernad.conf.
• It has a simple attribute value structure.

60
affordances and domains

• There are basically four things that an
  ernad-based current awareness system provides
  for.
• For each of these affordances, we have a
  separate domain.
• This allows for distinct affordances to be run by
  distinct domains.

61
the composition domain

• This is the domain used by the report issue
  composition interface.
• This is the virtual domain that the ernad apache
  is running under.
• The ernad process creates files so the apache
  server is best run as the user ernad.
• Recall ernad requires mod_perl, which in turn is
  incompatible with suexec.

62
the service domain

• This is where potential reader look at
  information about the ernad service
• what reports are available
• who edits them
• This domain is fixed through the reports
  configuration file report.amf.xml.

63
the list domain

• This is the domain where the mailing lists are
  under
• domain of web interface
• domain of the mailing lists
• Each report report has a list report_at_listdomain,
  where listdomain is the list domain.
• This domain is fixed through the reports
  configuration file report.amf.xml.

64
delivery domain

• The links to the full text use the encode the
  identifier of the paper and the identifier of the
  report.
• This allows to see what report readers requested.
  
• It is imperative that these links are not further
  disseminated. There should be no archives of nep
  lists.
• It is fixed in ernad.conf

65
reports.amf.xml

• The first part has the definition of NEP itself.
  (next slide)
• The second part as the definition of a report
  (slide after)?
• The allport is the first listed
• reports.amf.xml fixes
• report handles
• editor information, (incl. here editor ids)
• list domain
• service domain

66
ltamf xmlns"http//amf.openlib.org"
xmlnsxsi"http//www.w3.org/2001/XMLSchema-instan
ce" xsischemaLocation"http//amf.openlib.org
http//amf.openlib.org/2001/amf.xsd"
xmlnsernad"http//ernad.openlib.org"gt ltcollectio
n id"RePEcnep"gt lttitlegtNEP New Economics
Paperslt/titlegt ltaccesspointgt ftp//all.repec.org/
RePEc/wop/conf lt/accessointgtlthomepagegt http//nep.
repec.org lt/homepagegtlthaspartgt ltcollection
id"RePEcnepnepall"gt
67

• ltcollection id"RePEcnepnepcba"gtlttitlegt
• Central Bankinglt/titlegtlthomepagegt
• http//lists.repec.org/mailman/listinfo/nep-cba
  lt/homepagegtlternadpasswordgt...
• lt/ernadpasswordgtlthaseditorgtltpersongt
• ltnamegtAlexander Mihailovlt/namegtltname
  xmllang"en"gtAlexander Mihailovlt/namegt
• lthomepagegthttp//econpapers.repec.org/RAS/pmi59.ht
  mlt/homepagegt
• ltemailgt...lt/emailgtltispartofgt ltorganizationgt...lt/or
  ganizationgt
• lt/ispartofgtlt/persongtlt/haseditorgt
• lt/collectiongt

68
operation

• A rif always as a name yyyy-mm-dd_tist,
• where yyyy is the year, mm month, dd day of the
  nep-all issue.
• tist is a UNIX time stamp, i.e. the number of
  seconds that have passed since the first of
  January 1970
• rifs are never deleted. When an operation is
  made, a new version of the rif with a new tist is
  written.

69
creating a sri 0

• After login in to ernad, an editor sees a set of
  allport issues to work on.
• This is the report selection stage.
• If there is no allport issue needs working on a
  sorry message is displayed.

70
creating a sri 1

• When a subject report issue is created, it is
  copied from the source/ps or source/us directory,
  depending on whether the editor chooses with
  presorted to work with the presorted or the
  unsorted version of the report.

71
creating a sri 1.5

• If there is no paper worth to be included in the
  report, the editor can move back from the paper
  selection to the issue selection stage. There she
  can delete the issue.
• The rif of the issue is not deleted. Instead an
  empty issue is created in the final sent
  directory.

72
creating a sri 2

• Once papers have been selected, a rif is created
  in the into the director selected. This rif
  only contains the selected papers.
• If there are changes in the selections, new rifs
  are created, as soon as the editor moves to the
  next screen.

73
creating a sri 3

• Once papers have been ordered, a rif is created
  in the into the director ordered.
• If there are changes in the order, new rifs are
  created, as soon as the editor moves to the next
  screen.

74
creating a sri 4

• Once the sri has been previewed the editor can
  click the send button. The rif is stored in the
  sent directory.
• Ernad created a mail file containing a HTML and
  text version of the sri and places it in the
  mail directory.
• This file can be sent again if there is an email
  problem.

75
a lot of data

• ernad_at_khufu date
• Thu Oct 18 051837 EDT 2007
• ernad_at_khufu du -s ernad/var/reports/
• 24147956 ernad/var/reports/
• ernad_at_khufu find ernad/var/reports/ -type f
  grep -c
• 76043

76
maintenance

• Thomas Krichel has written a technical guide,
  mainly for the director and the general editor.
• It is at http//nep.repec.org/technical.
• It illustrates well that the technical
  maintenance is still quite heavy.
• A lot of maintenance scripts still have to be
  written by Thomas.

77
assessment

• How well does NEP work?
• Some criteria are already discussed the
  literature
• delay
• coverage ratio
• overlap

78
coverage to lossage

• There is a web site
• http//nep.repec.org/lossage
• that does show the papers that have not been
  sent, as well as the coverage ratio for each
  issue.
• It appears that coverage has improved.

79
overlap

• There is no script to compute current overlap
  data.
• There is quite good historical subscriber for
  most of the post-ernad period.
• Thus it is possible to calculate overlap of
  reports for various nep-all issues.

80
to improve coverage

• It would be interesting to redo the work of
  Krichel and Bakkalbasi (2005)?
• For English papers, we can try to presort nep-all
  issues for a virtual nep-no report. This could
  help to identify thematic gaps.
• We open language-specific reports?

81
delay

• The site http//nep.repec.org/delay shows average
  delays of editors.
• Half of the editors appear to do a good job. A
  good job is when the average delay is below a
  week.

82
editor activity

• There is a web site containing activity data of
  editors.
• http//nep.repec.org/editor_activity.
• There appear some minor problems but overall it
  appears ok.
• Date is only available from 2005-06, because of a
  misunderstanding between Roman D. Shapiro and
  Thomas Krichel.

83
downloads

• This is the ultimate measure of success.
• Downloads from a report can be measured because
  of a GCI parameter identifying the report.
• Parsing the logs and matching the handles with
  handles in reports is difficult.

84
downloads from issues

• A lot of downloads are made by editors when they
  compose the report issue.
• A lot of others are made by robots.
• As for the rest, data is at http//nep.repec.org/d
  ownloads
• At this time this is preliminary.

85
the Kiev framework

• This is a framework I want to discuss today to
  assess NEP.
• Objective maximize downloads of papers through
  NEP per paper announced.
• Means
• targeted report
• large and targeted audience
• both can be influenced by the editor

86
unit of assessment

• The unit of assessment is the report issue. This
  is not an assessment of
• the report
• the editor
• The independent variable is related to dependent
  variables through simple linear regression.

87
dependent variable

• It is the number of downloads made by users from
  a report.
• We try to get to the true user data.
• We only look at data after pre-sorting was
  introduced, say 2006 and 2007.
• In the following, I am looking at the independent
  variables (i.v.)?

88
i.v. of normalization

• i.v. 1 issue_size
• This is the number of papers in the report.
• i.v. 2 membership_size
• This is the number of members that the get the
  report just before the issue is mailed.

89
i.v. of membership

• One indication of membership quality it that is
  is dispersed.
• i.v. 3 concentration_1
• A measure of concentration of subscribers' top
  level domain.
• i.v. 4 concentration_2
• A measure of concentration of subscribers' top
  and second-level domain.

90
i.v. of timeliness

• i.v. 5 all_time
• the time between nep-all and the current subject
  issue
• i.v. 6 neighbour_time
• the minimum of
• the time between current issue and next issue
• the time between the current issue and and the
  previous issue

91
i.v. of composition

• i.v. 7 composition_duration
• the total time of composition
• i.v. 8 ordering_step
• the total number of times the report was ordered
• i.v. 9 trailer
• the position of the last paper selected
• i.v. 10 all_size
• the size of the corresponding nep-all

92
i.v. of season

• We know that the activity of RePEc is seasonal.
• i.v. 11 to 22 m1 to m12
• dummies to indicate the month

93
anything missing?

• the report?
• the editor?

94
Leonardo Fernandes Souto

• is a Brazilian PhD student working on current
  awareness services.
• He has (correctly) identified NEP as the model
  that all should follow -)?
• His questionnaire is at http//nep.repe
  c.org/research/NEP_questionnaire_2007-10-06.doc.

95
future extensions of ernad 1

• Use editor identities to build a customized
  experience length.
• Use a collection of multi-word RePEc keywords to
  aid pre-sorting.

96
future extensions of ernad 2

• Deal better with duplicate papers under different
  handles.
• use lists before ordering as a basis for
  inclusion into pre-sorting. This will allow
  editors to delete duplicates without confusing
  the SVM
• potentially detect duplicates at allport
  composition time.

97
future extensions of NEP

• Use RSS as an alternative dissemination method.

98
tough problems

• Filtering for new papers is deficient as the date
  on papers is not mandatory. Presorting for age
  seems impossible.
• The fight with spam is a problem for anyone who
  sends out a lot of mail.

99
finally stop the press...

• 2007-10-17 Christian Zimmermann wrote At
  http//ideas.repec.org/i/ e.html, I have
  attempted to classify registered authors by
  field. For this I used their papers as
  disseminated by NEP, and if at least one fourth
  are in a report, authors are considered to be a
  specialist of that field.

100
http//openlib.org/home/krichel

• Thank you for your attention!