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The Design of the Online Questionnaire
of the Italian Population Census
Leonardo Tininini
Antonino Virgillito
NTTS 2013
Brussels
March 5, 2013
The Design of the Online Questionnaire of the Italian Population Census,- Tininini & Virgillito - Brussels, March 5, 2013
2
Outline
• The QPOP Online Questionnaire: the Requirements
• The Design of QPOP
• The Questionnaire Graph
• The Online Questionnaire Usage Statistics
• Conclusions and Future Work
The Design of the Online Questionnaire of the Italian Population Census,- Tininini & Virgillito - Brussels, March 5, 2013
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The QPOP online questionnaire: the requirements
• To be used by both citizens and operators (by SSO)
• Tight integration with the Census Management System,
particularly the Census - Register comparison
(Poster Session Mar 7, 12:00-13:30)
• Reproducing the 3 paper questionnaries
– short / long form for households + form for collective dwellings
• Each in 3 languages (Italian, German and Slovanian)
• Very stringent requirements of robustness, scalability, data
quality
...therefore
almost impossible re-using or adapting an off-the-shelf product
The Design of the Online Questionnaire of the Italian Population Census,- Tininini & Virgillito - Brussels, March 5, 2013
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The Design of QPOP
• Write more metadata (and less programming code)
– question templates (graphical rendering but also processing)
– question routing (achieved by Questionnaire Graph)
• Assisted coding of open (textual) questions
– search engine on highest educational qualification (6,000 items)
– dictionary pre-processing, similarity string comparison + result ranking
• Robustness, scalability and data quality
– open source frameworks: Struts2, Spring and Hibernate
– extensive use of caching to limit DB access
– quality checks on both client and server side
The Design of the Online Questionnaire of the Italian Population Census,- Tininini & Virgillito - Brussels, March 5, 2013
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The Questionnaire Graph (QG)
• Formal description of question routing by Directed Acyclic Graphs
– nodes = questionnaire fragments (questions, but not only)
– labeled edges = go from node 1 to node 2 if the “label” is true
• Simple syntax, easy to be evaluated, yet powerful
– quantification, counting, composition mechanisms...
• Used on both client (Javascript) and server (Java) side
– enable/disable questions, compilation checks
• Each node is associated with a “state” (filled-in, unreachable, ...)
– each node state changes continuously during compilation as it
depends on both the QG and the answers already given
– changes in the answers triggers the recomputation of node states
The Design of the Online Questionnaire of the Italian Population Census,- Tininini & Virgillito - Brussels, March 5, 2013
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From the questionnaire to the QG
The Design of the Online Questionnaire of the Italian Population Census,- Tininini & Virgillito - Brussels, March 5, 2013
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Node states and state recomputation
The Design of the Online Questionnaire of the Italian Population Census,- Tininini & Virgillito - Brussels, March 5, 2013
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Node states and state recomputation in action (1)
The Design of the Online Questionnaire of the Italian Population Census,- Tininini & Virgillito - Brussels, March 5, 2013
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Node states and state recomputation in action (2)
The Design of the Online Questionnaire of the Italian Population Census,- Tininini & Virgillito - Brussels, March 5, 2013
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Node states and state recomputation in action (3)
The Design of the Online Questionnaire of the Italian Population Census,- Tininini & Virgillito - Brussels, March 5, 2013
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QPOP Usage statistics (1)
Usage % for the possible means of returning
the Census questionnaire
33,4%
31,7%
22,6%
12,3%
Online quest.
Municip. c.c.
Post offices
Enumerators
0,00%
1,00%
2,00%
3,00%
4,00%
5,00%
6,00%
7,00%
8,00%
9,00%
10,00%
00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16 17 18 19 20 21 22 23
Preferred means (33.4%) of returning the
Census questionnaire:
~ 8.5 million household questionnaires
corresponding to:
~ 20 million individuals
~ 30 “partial saves” (on average) for each
completed questionnaire
Majority of access during
office hours
• agreement with the
Public Administrations
• PCs made available by
Municipality Offices
Overall hourly distribution of online questionnaire completion
The Design of the Online Questionnaire of the Italian Population Census,- Tininini & Virgillito - Brussels, March 5, 2013
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QPOP Usage statistics (2)
0 200.000 400.000 600.000 800.000 1.000.000 1.200.000 1.400.000
Week 10
Week 09
Week 08
Week 07
Week 06
Week 05
Week 04
Week 03
Week 02
Week 01
Number of completed online questionnaires in the first 10 weeks
Maximum load was measured during
the first week
• up to 500/minute questionnaires
completed
• up to 20,000/minute partial saves
(and up to 500/second)
Anomalous peak during the 6th
week
• misinterpretation of a date in the
first page of the form?
• starting date for the enumerators’
activity?
• ....?
The Design of the Online Questionnaire of the Italian Population Census,- Tininini & Virgillito - Brussels, March 5, 2013
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Conclusion and future works
• Good design practices resulted in:
– High percentage of online-returned questionnaires
– Good stability of the system, even during peak periods
– Easy re-use...
• ...from QPOP to the online questionnaire for the Industry and
Services Census (Sep 2012 – Feb 2013)
– 3 different questionnaires (much more complex than QPOP)
– ~ 70% compiled by end users (+ 30%, also online, by operators)
• The future
– The (paperless) rolling Censuses (first pilot in 2014)
– Graphical User Interface to facilitate Questionnaire Graph Design