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					                             Summary of day 1
Social Network Analysis



                             • Introduction to Knowledge Mapping
                               and Social Network Analysis (SNA)
                             • The importance of asking the right
                               question




                                       Questions ?
                      4- 1
       Social Network Analysis




4- 2
                                 Day 2
                               Session 4
Social Network Analysis


                                    -
                             Data collection




                               Steeve Ebener, WHO
                                Manila, Philippines
                                 28-30 April 2008
                      4- 3
                                             Content
Social Network Analysis

                             1. Which data to collect
                             2. Source of the data
                             3. Ego vs Full network
                             4. Ego network data
                                collection
                             5. Full network data
                                collection
                             6. Data collection
                                Instrument
                             7. Data issues
                             8. Example of the DTTB
                                project
                      4- 4
                                Which data to collect ?
                             Several types:
Social Network Analysis



                             • data about the respondent
                               (demographics)
                             • network specific questions (see previous
                               session)
                             • any additional information which might
                               be useful for the analysis
                               – case of the Ego networks
                               – example of the DTTB project




                      4- 5
                                   Which data to collect ?
                             Data about the respondent (demographics)
Social Network Analysis



                             Examples:
                               •   income
                               •   education
                               •   location (birth,
                                   assignment,...)
                               •   gender
                               •   age
                               •   ethnicity
                               •   religion
                               •   occupation
                               •   ...


                      4- 6                                     Valente
                                  Which data to collect ?
                             Other data of importance for the analysis
Social Network Analysis



                             Examples:               DTTB project:
                             •   Cultural values;    •  Access to internet
                             •   Competency areas;   •  Area of expertise they have
                                                        been looking for
                             •   Use of different
                                 types of media      •  Number of experts they
                                 (online, printed,      knew before being deployed
                                 face-to-face) for   •  Electricity availability
                                 getting             •  Name of the referral facility
                                 information.        •  What to improve in the DTTB
                                                        program
                                                     •  time and reason of contact


                                                        + Experts directory
                      4- 7
                                    Source of the data
                             Secondary data (often 2 mode)
Social Network Analysis



                             • Memberships in groups
                               – Facebook "networks"
                             • Participation in events
                               – Listserv threads
                               – Voting records
                             • Text analysis
                             • Other
                               – Email records, purchase/sale records,
                                 marriage records, etc... (patient
                                 records?)


                                                                     Borgatti
                      4- 8
                                    Source of the data
                             Primary data
Social Network Analysis



                             • Experiments
                               – Rumor planting
                             • Observation
                               – Westen-Electric Hawthorne plant
                                 studies
                             • Survey/Census/Logbook
                               – Telephone, web, paper, etc
                               – example of the DTTB project




                                                                   Borgatti
                      4- 9
                                        Ego vs full network
                              Ego Network data collection
Social Network Analysis


                              •   interview of the respondents (egos) to ask
                                  about their contacts (alters)
                                  –   The alters are not interviewed
                                  –   One ego's alters are not matched up with other
                                      egos or their alters
                              •   Collect a lot of (perceived) info on the alters

                              Full Network data collection ("regular"
                                 SNA)
                              •   interview of the respondents and their
                                  contacts
                              •   Do generally not collect info on the alters
                                                                                 Borgatti
                      4 -10
                              Ego vs full network
Social Network Analysis




                                                    Borgatti
                      4 -11
                                  Ego Network data collection
                              •    Characterize the relationship with
Social Network Analysis


                                   each alter
                              •    Optionally obtain ego's perception of
                                   which alters have ties with other
                                   alters
                              •    Connections between ego's or
                                   between alters of different egos are
                                   not collected




                                                             Modified from Borgatti
                      4 -12
                              Full Network data collection
                              Survey vs Census
Social Network Analysis


                              •   in a survey only part of the network is
                                  interviewed
                                  –   sampling issue (still in its infancy)
                                  –   data analyzed but not graphed
                              •   in a census all the network is interviewed
                                  –   saturation sampling
                                  –   The most typical kind of network methodology
                                  –   Usually what people think of when we say
                                      networks.
                                  –   These data can be graphed and analyzed using
                                      matrix methods


                                                              Modified from Borgatti and Valente
                      4 -13
                              Full Network data collection
                              Survey - Sampling
Social Network Analysis


                              •   Fixed probability (e.g. random sampling)
                                  –   Fine with Ego Network
                                  –   Ok for some complete network studies
                              •   Adaptive sample (e.g. snowball sampling)



                                        Red nodes are interviewed alters
                                        Blue node are not Interviewed

                              •   Stances
                                  –   Nominalist/etic (least delusional approach)
                                  –   Realist/emic (best used for true groups)
                                  –   Combination
                                                                  Modified from Borgatti and Valente
                      4 -14
                              Full Network data collection
                              Survey – sampling (Stance)
Social Network Analysis




                                                           Borgatti
                      4 -15
                              Full Network data collection
                              Census
Social Network Analysis


                              •   Unknown network
                                  –   Ask for the help of one or several of the members
                                  –   Use the snowball approach to identify all the
                                      members
                              •   Known network
                                  –   Interview all the members

                              Avoid survey when possible !




                                                                       Borgatti and Valente
                      4 -16
                              Data collection instruments
                              Ethical Issues
Social Network Analysis


                              • Respondents cannot be anonymous
                              • Snowball sampling ask respondent to name others
                                  –   "bill says that you inject illegal drugs with him, can we
                                      talk to you ?
                              • Missing data are troublesome
                                  –   Might put the attention on the wrong issue
                                  –   Results may be wrong
                              • Non-participants still included as mentioned by others
                                  –   And participants are like informers
                              • Outputs ideally show individual level data
                              • Pushes boundary of the professional
                              • Deceptively powerful
                                  –   SNA is still unknown, look like research
                              • Quid pro quo arrangements with research sites
                      4 -17
                                  –   Management might hire/fire based on results       Borgatti
                              Data collection instruments
                              Ethical Issues
Social Network Analysis



                                    Need to find out what are the
                                    potential ethical threat and to
                                    whom ?
                                      •   In academic setting
                                      •   In management setting
                                      •   In mixed situations
                                      •   In national security setting
                                      •   ...

                                    Need to address them


                                                                         Borgatti
                      4 -18
                              Data collection instruments
                              Ethical Issues
Social Network Analysis


                              • Consent form, disclosure contract
                              • Anonymizing (not releasing demographic data for
                                example)
                              • Address non-participation
                              • Aggregating & categorizing
                              • Avoid Quid pro quos
                              • Find the good time to perform the analysis (not before a
                                restructuration for example)
                              • Protect data (e.g. theft)
                              • Organization consulting (who gets to see the data ?,
                                professional debriefing,...)
                              • ...


                                                                                Borgatti
                      4 -19
                              Data collection instruments
                              Ethical issues
Social Network Analysis



                                   Truly informed consent form




                                                                 Borgatti
                      4 -20
                               Data collection instruments
                               Ethical issues
Social Network Analysis



                                        3-way disclosure contract

                              • For research done
                                in organizations
                              • Signed by
                                management,
                                the researchers,
                                and each
                                participants
                              • Clearly identifies
                                what will be
                                done with the
                                data
                                                                    Borgatti
                      4 -21
                              Data collection instruments
                              Ethical issues
Social Network Analysis



                                   Questionnaire might also have to go
                                   through the ethical committee's
                                   approval
                                   Confidentiality reminder on the
                                   questionnaire




                                                                     Borgatti
                      4 -22
                              Data collection instruments
                              Which instrument ?
Social Network Analysis



                              • Data about the
                                respondent
                                (demographics)
                              • Network specific      Questionnaire +
                                questions                 form(s) if
                              • Any additional         performed once
                                information which
                                might be useful for
                                the analysis
                                Wants to do it          Logbook
                                 over time ?
                                                      DTTB project
                      4 -23
                              Data collection instruments
                              Questionnaire format
Social Network Analysis


                              General questionnaire rules also applies here
                              (e.g. importance of the order of the questions)

                              Some specific issues:
                              • Aided (rosters) vs unaided (open-ends)
                              • Tick, rate or rank ?
                              • Across (Multigrids) or down (separated
                                questions)
                              • Paper or electronic



                                                                         Borgatti
                      4 -24
                              Data collection instruments
                              Closed-Ended vs Open-Ended
Social Network Analysis


                              Roster of names or just blank lines ?

                              • Closed-ended (aided)
                                   –    requires bounded list
                                   –    Can be impractical for
                                        large network
                                   –    Each alter has ~equal
                                        chance of choice
                              • Open-ended (unaided)
                                   –    Subject to recall errors
                                   –    can limit number of
                                        choices made
                                   –    (more effort, limited
                                        space)

                      4 -25            use hybrid designs otherwise   Borgatti
                              Data collection instruments
                              Hybrid Questionnaire
Social Network Analysis


                              • Paper questionnaire with a separated
                                booklet containing name directory
                              • Web version questionnaire with drop-
                                down menus

                                Hybrid designs
                                are useful in
                                large networks

                                Importance to
                                use a unique ID
                                to cover name
                                writing mistakes



                                                                       Borgatti
                      4 -26
                              Data collection instruments
                              Tick, rate or rank ?
Social Network Analysis


                              • Ask respondent for yes/no decisions or quantitative
                                assessment ?
                                  –   Yes/no are easier on respondents (therefore reliable,
                                      believable
                                  –   Yes/no "much" faster to administer
                                  –   But yes/no provides no discrimination among levels –
                                      ratings provide more nuance
                              • A series of binaries can replace on quantitative rating:
                                  –   Instead of "How-often do you see each person?"
                                       •   1= once a year; 2 = once a month; 3= once a week; etc.
                                  –   Use three questions (in this order):
                                       •   Who do you see at least once a year ?
                                       •   Who do you see at least once a month ?
                                       •   Who do you see at least once a week ?


                                                                                          Borgatti
                      4 -27
                              Data collection instruments
                              Tick, rate or rank ?
Social Network Analysis


                              • Users asked to rank others in terms of communication
                                frequency over 3 weeks
                                  –    person most communicated with was ranked in top 4
                                       only 52 % of time
                                  –    Accuracy of prediction s of the next month's
                                       communication was the same, who you like = who you
                                       talk to
                              • All studies taken together had similar results
                              • Studies in other fields corroborate

                                      Ranking can give unreliable results !




                                                                                   Borgatti
                      4 -28
                              Data collection instruments
                              Repeated Roster vs MultiGrid
Social Network Analysis




                                                             Borgatti
                      4 -29
                              Data collection instruments
                              Paper or electronic ?
Social Network Analysis


                              • Paper medium
                                  –   Reliable
                                  –   Reassuring to respondents
                                  –   Possible errors in data entry
                                  –   Data entry is time-consuming
                                  –   ...
                              • Electronic (Pda, Web)
                                  –   Span distances, time zones
                                  –   harder to lose
                                  –   Fewer data handling errors
                                  –   Possible lower response rate
                                  –   Emailed documents (e.g. excel file) vs online survey
                                      instrument
                                  –   ...

                      4 -30
                                      Choose what is most adapted                     Borgatti
                              Data collection instruments
                              Design Considerations
Social Network Analysis


                              • Network questionnaires can be fun but are usually time-
                                consuming and might generate anxiety
                                  –    Providing value
                                  –    Treating respondents with respect
                                  –    Attractive formatting
                                  –    Cloak in authority and importance
                              • Do not forget that multiple, similar relational questions
                                risk respondent fatigue and annoyance
                                  –    Who do you give advice to ?
                                  –    Who do you give information to ?
                                  –    Who do you give guidance to ?
                                  –    Who do you counsel ?

                                      Aggregation to larger categories, such as
                                      affective & instrumental can work well
                                                                                  Borgatti
                      4 -31
                                                 Data issues
                              Information accuracy
Social Network Analysis


                              • Response strategies and biases
                                  –    Appearing central
                                  –    Recalling important people more than others
                                  –    Hiding illicit relationships
                              • Cognitive & cultural schemas
                                  –    Recall biased towards normal, frequent, logical
                                  –    Role schemas filter perceptions, learning


                                      Can't do much about it but need to be
                                      aware of it
                                      Ethnographic sandwich


                                                                                         Borgatti
                      4 -32
                                                Data issues
                              Unexpected asymmetry
Social Network Analysis


                              • A claims to have sex with B, but B does not claim to
                                have sex with A
                                  –   The relation is logically symmetric, but empirically
                                      asymmetric
                                  –   can be an error in the recall, strategic response
                              • Sometimes asymmetry is the point
                              • Logically symmetric data may be symmetrized
                                  –   if either A or B mention the other, it's a tie

                              ! Can't symmetrize logically non-symmetric
                                relations (e.g. gives advices to), unless
                              • changing the meaning of tie
                              • you have asked the question both ways (who do
                                you give advice to ?, who gives advice to you ?)
                                                                                        Borgatti
                      4 -33
                                                 Data issues
                              Missing data
Social Network Analysis


                              • Quick and dirty
                                  –   For logically symmetric relations
                                       •   if B-A tie is missing, substitute A-B tie
                                  –   For logically non-symmetric relations, ask questions
                                      both ways (see previous slide)
                              • Bayesian imputation methods (not addressed here)




                                                                                       Borgatti
                      4 -34
                              Example of the DTTB Project
                              Ego or Full network data collection ?
Social Network Analysis


                              •   Known network
                                  –   2 Batches (18 in Batch 21 and 16 in Batch 22)
                              •   A DTTB doctors can contact and other DTTB
                                  doctor or an outside expert. Further contacts
                                  made by outside experts are not captured
                                  –   mixed Ego (contact with experts) and full network
                                      (among DTTBs) analysis
                                  –   use of expert information form
                              •   Question: who do you contact for medical
                                  expertise ?
                                  –   Expertise network analysis
                              •   Data collected over a period of 9 months
                                  –   time dimension
                      4 -35
                                                                   Mixed approach
                              Example of the DTTB Project
                              Questionnaires and forms
Social Network Analysis



                                             Questionnaire Batch 21- 22
                                                 Questionnaire
                                                 previous Batches
                                                         Experts contact
                                                         form




                      4 -36
                              Example of the DTTB Project
                              Logbook
Social Network Analysis




                      4 -37

				
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