TECHNIQUES

Individual Level Density

Measure in Social Network Analysis representing the degree in which a respondent's ties know one another/ proportion of ties among an individual's nominees. Network or global-level density is the proportion of ties in a network relative to the total number possible (sparse versus dense networks).

Item Response Theory

Item response theory is a body of theory used in the field of psychometrics. Pychometrics is concerned with the theory and technique of educational and psychological measurement. In item response theory (IRT), mathematical models are applied to analyze data from questionnaires and tests as a basis for measuring things such as abilities and attitudes studied in psychometrics.

IRT models are mathematical functions that specify the probability of a discrete outcome, such as a correct response to an item, in terms of person and item parameters. Person parameters may, for example, represent the ability of a student or the strength of a person's attitude. Items may be questions that have incorrect and correct responses, or statements on questionnaires that allow respondents to indicate level of agreement.