TABLE 1—
Tested Effects of Network and Behavior Coevolution Models of Peer Selection and Influence on Adolescent Smoking and Drinking: Social Network Study, 2010–2011
| Effect | Description |
| Network dynamics (selection) | |
| Rate parameter—friendship | Average number of opportunities for tie changes over time |
| Endogenous structural effects | |
| Out-degree (density) | Tendency to form friendship with someone |
| Reciprocity | Tendency to form friendship with someone who previously selected participant as friend |
| Transitivity | Tendency to form friendship with a friend of a current friend |
| 3 cycles | Tendency for network closure between 3 friends |
| Covariate effects (similarity) | |
| Female, grades, Hispanic | Tendency to form friendship with someone of the same gender, with similar academic grades, and with someone who is of Hispanic/Latino descent |
| Online risky pictures | Tendency to form friendship with someone who has similar exposures to friends’ online posts of risky pictures |
| Online partying | Tendency to form friendship with someone who has similar exposures to friends' online discussions about partying |
| Tendency to form friendship with someone who has similar Facebook use habits | |
| MySpace | Tendency to form friendship with someone who has similar MySpace use habits |
| Behavioral effectsa | |
| Behavior alter (popularity) | Effect of behavior on tendency to receive ties |
| Behavior ego (activity) | Effect of behavior on tendency to send ties out |
| Similarity in risk behavior | Effect of 2 people selecting each other as friends on the basis of similarity in behavior |
| Behavior dynamics (influence) | |
| Rate parameter—behaviora | Average number of opportunities for changes in behavior over time |
| Linear tendency | Linear distribution of behavior |
| Quadratic tendency | Quadratic distribution of behavior |
| Behavioral effects | |
| Behavior alter average | Effect of the average of friends’ behaviors on participants' behavior |
| Female | Effect of being female on behavior |
| Grades | Effect of grades on behavior |
| Parental smoking/alcohol use | Effect of parental smoking or alcohol use on behavior |
| Hispanic/Latino | Effect of being Hispanic/Latino on behavior |
| Friends post risky pictures online | Effect of friends’ online posts of risky pictures on behavior |
| Friends talk about partying online | Effect of friends’ online discussions about partying on behavior |
| Effect of Facebook use on behavior | |
| MySpace | Effect of MySpace use on behavior |
| Current risk behavior | Effect of other risk behavior (smoking or alcohol use) on behavior |
a
Behavior parameters refer to either smoking or alcohol use.