Table 3.

Features capturing levels of individual, relationship, and community–level activity within Twitch channels. Unless otherwise specified, features capture aggregated activity over the 28-day period preceding survey deployment. A ‘visit’ is defined as five or more minutes spent in the channel during a given session, and a ‘viewer’ is defined as an individual with one or more visits. Variables marked as ‘log-scaled’ were transformed as log₂(x).

Social-Ecological Model Levels		Independent Variables : Behavioral Traces
Level	Description	Construct	Measure	Description
Individual	Features describing the individual viewer’s engagement.	Individual Sitewide Activity	Sitewide Tenure	Total days since initial account creation [log-scaled]
			Sitewide Visit Days	Unique days with visits on Twitch (any channel)
			Sitewide Chat Days	Unique days with chat activity on Twitch (any channel)
		Individual Channel Engagement	Channel Tenure	Total days since first visit to channel [log-scaled]
			Channel Visit Frequency	Fraction of sitewide visit days with channel visit
			Channel Visit Duration	Average session length per channel-day visited [log-scaled]
		Individual Channel Participation	Chat Volume	Total number of chat messages sent in channel [log-scaled]
			Chat Visibility	Total fraction of time in channel with chat visible
			Peripheral Participation	True, if viewer has participated using affordances outside of chat, such as polls or channel points; False, otherwise
Relationship	Features describing the viewer’s dyadic interactions with others in the community.	Viewer-Viewer Relationship	Has Sent Mention	True, if viewer has mentioned in chat at least one other community member; False, otherwise
			Has Received Mention	True, if viewer has been mentioned in chat by at least one other community member; False, otherwise
		Viewer-Creator Relationship	Has Cheered	True, if viewer has “tipped” or “cheered” at least once using bits; False, otherwise
			Has Paid Subscription	True, if viewer had an active paid subscription to the channel at any point during the data collection period; False, otherwise
			Has Prime Subscription	True, if viewer had a Prime subscription to the channel at any point during the data collection period; False, otherwise
Community	Features describing the broader social environment within the channel.	Community Composition	Fraction Logged-In	Average daily fraction of viewers who are logged in to an account (log-scaled)
			Fraction Regulars	Average daily fraction of logged-in viewers who have viewed the channel at least once before, within the prior 28 days (log-scaled)
			Average Tenure	Average number of days since the first visit to the channel among logged-in viewers (log- scaled)
		Community Collective Interaction	Fraction Chatters	Average daily fraction of logged-in viewers who sent at least one chat message
			Chat Intensity	Average number of daily chat messages sent per chatter (log-scaled)
			Has Mentions	True, if 1 or more mentions were sent in chat during the data collection period; False, otherwise
			Fraction Global Emote Users	Average daily fraction of chatters who used at least one global emote
			Fraction Sub Emote Users	Average daily fraction of chat users who used at least one subscription emote
			Peripheral Participation	True, if channel has any viewers who participated using affordances outside of chat, such as polls or channel points; False, otherwise
		Community Creator Interaction	Paid Subscription Rate	Average daily fraction of logged-in viewers with a paid subscription
			Prime Subscription Rate	Average daily fraction of logged-in viewers with a Prime subscription
			Gift Subscription Rate	Average daily fraction of viewers who have gifted 1+ subscription to another viewer in the channel.
			Cheer Rate	Average daily fraction of viewers who have “cheered” or “tipped” the creator using bits.
		Overall Channel	Channel Age	Months since the first broadcast on the channel
			Live CCU	Average live concurrent viewers, as computed over the data collection period (log-scaled)
			Broadcast Frequency	Fraction of days during data collection period where channel broadcast live for 5 or more minutes