4. Performing and organising t tests

Stata's ttest function does not work on Gini coefficients, which have their own standard error. For this reason, the t-statistics of the Ginis have to be computed via Python. So, the file enriched with the cross-runs mean and standard errors of the two Gini coefficients is processed by a Python script.

T-tests on the other variables are performed in Stata. Their results are then merged with those of the Python script.

The form of the output is:

[
 {
    'parameter1': value, ...,
    'tTest_policy_more_active_vs_newer': tStatValue, ...,
    'tTest_priority_more_active_vs_newer': tStatValue, ...
  }
]

• The first line describes the input parameters of the NetLogo model.
• The second line describes the result of the t-tests on all tracked variables

Parameters:

1. globalchattiness (.1, .2, .4). The probability that a member of the online community will be active attime t, even if she did not receive any comment at t - 1.
2. intimacystrength