Trends over time along four dimensions of specialization.

The distributions of (a) focus, (b) rarity, (c) novelty, and (d) technical exclusivity over time suggest that each measure captures a different dimension of specialization. Meetup groups trend towards associating with rarer topics, and the introduction of new topics declines over time.</p

Meetup groups with the most and least common topics across the years they were active.

Meetup groups with the most and least common topics across the years they were active.</p

Linear model of group performance predicted by topic focus.

Coefficient estimates of cross-sectional linear regression models for predicting a group’s size, growth, audience retention, and survival, using a group’s topic focus score as the lone predictor.</p

Cross-sectional linear regression model of group performance predicted by multiple dimensions of specialization.

The table reports coefficient estimates for predicting a group’s size, growth retention, and survival using a group’s topic focus, rarity, novelty and technical exclusivity scores.</p

Meetup groups with the most and least technical topics.

Meetup groups with the most and least technical topics.</p

RData file with data frames all analyses.

Curated data frame for components of the focus score calculation named focustfidf. Curated data frame for main regressions named groupstatic. Curated data frame for survival analysis named survdata in the data file. (ZIP)</p

Topics listed by the NY Tech Meetup group.

NY Tech Meetup hosts events bringing together interested technologists in the metropolitan region to share ideas related to the technology economy. Topic tags highlighted here are circled at the bottom of the figure.</p

Technical appendix that discusses alternative specifications of focus and robustness check of the Cox proportional hazards assumption for survival models.

Technical appendix that discusses alternative specifications of focus and robustness check of the Cox proportional hazards assumption for survival models.</p

Pairwise correlations among four measures of specialization in the topic profiles of Meetup groups.

Focus, rarity and novelty are positively correlated with one another but the pairwise correlations are relatively small. Tehnical exclusivity is negatively correlated with rarity and novelty.</p

Meetup groups with the most and least focused topics based on their choice of proximal topics.

Meetup groups with the most and least focused topics based on their choice of proximal topics.</p