Archival data analysis

The goal of this study is to assess the relationship between individual aspects of a user’s online be-havior and sustainability measures. Following our proposed framework, we focused on measures of online activity, social network position, and content at the individual level. To assess sustain-ability, we defined measures of performance and retention at the individual level. To compute these measures, we used archival data of the posts that were exchanged in 35 E-Democracy online forums for neighborhoods and districts in the cities of Minneapolis and St. Paul from 2008 until the second quarter of 2014.

We focused our analysis on posts that initiated new threads in the forums; therefore, we could reasonably assume that other posts in the same thread were responses (a measure of performance of generating content). For each initial post, online response was represented as a binary variable with values of one if the initial post had received at least one answer, and zero otherwise.

Retention was measured as other binary variables that represent whether the user posted again in the forum within a timeframe of 25 days (the average time between two consecutive posts of a user) and of a quarter (to discuss these results in comparison with the prior study - Chapter 6).

These variables were called within avg. and within quarter. We also considered another binary measure of retention that indicates whether the user never posted again in the forum and migrated to another forum within the E-Democracy platform.

We measured the independent variables at the time of posting. For each post that initiated a new thread in the neighborhood forums, we computed several measures that describe the characteristics of the post’s author at the time of the post. In regard to the user’s online activity, we computed the user’s level of contribution in the current forum as an ordinal variable with three values: (1) newcomers with zero prior posts; (2) old-timers with a number of prior posts between one and 37;

and, (3) power-users with more than 37 prior posts. We chose the threshold of 37 posts (the 95th

percentile) to have a balanced number of observations in the old-timer and power-user groups. We also defined a binary indicator of membership overlap that represents if the user had posted to another E-Democracy forum in the same quarter.

Additionally, we used the results of our social network analysis (see Sections6.1.4and6.2.4) and automatic classification of content (see Sections 6.1.5 and6.2.5) to add these aspects to our individual-level analysis. Two network position measures were considered at the time of posting:

the degree centrality of the user and to what extent they were a broker in the forum’s social net-work. The broker position was determined by the network constraint index, as suggested by prior literature [16, 17, 18]. Regarding content, we included the predicted kind of content of the post, including three possible values: non-mobilization, passive mobilization and active mobilization.

To estimate retention measures, we included a binary variable that describes whether the last post of a user received a response. To control for the level of activity in the forum (a collective measure), we included the number of users who had contributed to the forum in the past. Table43 summarizes the independent and dependent variables of this analysis.

7.1.2 Descriptive statistics

Our analysis of the archival data indicates that 3,466 individuals have initiated a new thread of conversation at least once in a neighborhood forum. Together, these users created 32,903 new threads. In response to these initial posts, a total of 42,471 other posts were generated by the online groups.

The analysis also reveals that about a third (35.4%) of the new threads received a response in the neighborhood forum. Nevertheless, 67% of the authors of those initial posts contributed again within 25 days and 80% within a calendar quarter. Only 4.7% of people who posted in a neighborhood forum stopped posting in the forum and migrated to another E-Democracy forum (see Table44).

The distribution of posts by contributors is right-skewed, as is the case in most participatory information systems [69, 114]. On average, users created 9.5 posts that initiated new threads in a forum, ranging from 1 to 1,168 and with a median value of two posts. Ten percent of the posts were created by newcomers, slightly more than half were posted by old-timers, and the remaining

Table 43: Independent and dependent variables of archival analysis of study 2

Independent variables Dependent variables

1. Users’ online activity in the forums a. Prior level of contribution b. Membership overlap 2. Network position in the forum

a. Centrality b. Brokering 3. Content

a. Kind of shared content b. Responded

1. Performance

a. Got a response?

2. Retention

a. Posted again within average time?

b. Posted again within a quarter?

c. Migrated to another forum?

were added by power-users. Among the 3,466 unique contributors who had started at least one thread of conversation in the neighborhood forums, 68% (2,359) had posted exclusively in one neighborhood forum, and another third of the contributors had posted to more than one forum.

People who posted in more than one forum were often power-users.

Regarding the network position of the users, the degree centrality ranges from 0 to 624 with an average of 65. The measure network constraint that represents a user brokerage position varies from 0 to 1.281 and its average is 0.166 (st. dev. = 0.221). This indicates that there is little variation on the brokerage position of the users in the forums’ networks.

With respect to the kinds of content, 47% of the posts that initiated a thread were active mobi-lizations, 33% of them were passive mobimobi-lizations, and the remaining were non-mobilizations.

Table 44: Descriptive statistics of online measures of sustainability at the individual level

Dependent variable Mean Std. Dev.

Received a response 0.354 0.478

Posted again within avg. time 0.670 0.47 Posted again within a quarter 0.803 0.398 Migrated to another forum 0.047 0.211