Item Response Theory (IRT) scale scores. The ECLSK:2011 direct cognitive assessment employed a two-stage design. As such, within any given domain, children received a routing set of items (stage 1) and then, based on their performance on the routing items, proceeded to a second set of items of a certain difficulty level (stage 2). Because not all children received all items, the assessment scores were modeled using IRT. Based on children’s performance on the items they received, an ability estimate (theta) was derived for each domain. The IRT scale scores represent estimates of the number of items children would have answered correctly if they had received all of the scored questions in a given content domain. They are useful in identifying cross-sectional differences among subgroups in overall achievement levels and provide a summary measure of achievement useful for correlational analysis with status variables. The IRT scale scores are also used as longitudinal measures of overall growth.
Race/ethnicity. Office of Management and Budget guidelines for collecting information on race and ethnicity were followed under which a respondent could select one or more of five dichotomous race categories when reporting their own race or that of their child. Each respondent additionally was asked to identify whether he or she (as well as the study child if the respondent was a parent) was Hispanic. The study data files include several variables indicating race and ethnicity. There are six dichotomous race variables indicating whether a respondent or study child was of a certain race (White, Black, Asian, Native Hawaiian or Other Pacific Islander, American Indian or Alaska Native, and more than one race) as well as one dichotomous ethnicity variable indicating whether a respondent or study child was Hispanic. These variables were used to create one race/ethnicity composite variable with mutually exclusive categories: White, not Hispanic; Black, not Hispanic; Hispanic of any race; Asian, not Hispanic; Native Hawaiian or Other Pacific Islander, not Hispanic; American Indian or Alaska Native, not Hispanic; and Two or more races, not Hispanic. In later rounds, more detailed information was collected if the child was Hispanic, Native Hawaiian or Other Pacific Islander, or another Asian subgroup.
Socioeconomic status (SES). The ECLS-K:2011 data file provides a measure of SES reflecting the SES of a child’s household at the time of data collection. The components used to create the SES variable are parent 1’s education, parent 2’s education, parent 1’s occupational prestige, parent 2’s occupational prestige, and household income. Each parent’s occupation was scored using the average of the 1989 General Social Survey (GSS) prestige scores for the 1980 census occupational category codes that correspond to the ECLS-K occupation code. New technology jobs that came into existence since 1989 were appropriately coded1.
1 For example, “website developer” was included in the “Other technologist/technician (except health)”; “website sales” was in “Marketing/Sales”; and “run web printer” was in “Other production occupation.” |