Technical Manual - Renaissance Learning

ValiditySTAR Early Literacy Enterprise Research Study ProceduresStudents’ age and grade. Age was available only for the 4,421 students whosedates of birth were recorded; grade was available for all 7,404 students withcompleted Enterprise tests. Data were available for students in grades pre-Kthrough 5; however, the samples sizes were too small for analysis in anygrades except Kindergarten through 3.Teachers’ ratings of 6,720 students on the 10 CCSS-aligned literacy skills.Scores on the rating survey were for all of those students.ResultsEquivalence of STAR Early Literacy Enterprise and Service VersionsTable 36 lists summary statistics on Enterprise and service scores—includingRasch ability and Scaled Scores—for all grades combined, including grades pre-Kthrough grade 5. The scores for the service version are averages of 1 to 3 scoresrecorded during the research testing window; students with more than 3 servicetests during the research window were excluded from all analyses in this section.The mean Enterprise Scaled Score was 755, 13 points higher than the averageScaled Score on the service version, 742. Similarly, the mean Enterprise Raschability score was 1.88, which was 0.18 logits (Rasch scale units) higher than theservice version average of 1.70.Table 36:Summary Statistics on Enterprise and Service Tests, All Grades CombinedVariable N Mean Standard DeviationEnterprise Scaled Score 7,070 755 104Enterprise Rasch Score 7,070 1.88 1.37Average Service Scale Score 7,070 742 106Average Service Rasch Score 7,070 1.70 1.33Table 37 displays the intercorrelations of the Enterprise test scores with theservice version scores for all grades combined. The correlation between the ScaledScores was 0.78; between the Rasch ability scores, the correlation was 0.80. Allcorrelations were statistically significant (p < 0.0001).Table 37:Correlations between Enterprise Test Scores and Average Service VersionScores, All Grades Combined, N = 7070Average ServiceScaled ScoreAverage ServiceRasch ScoreEnterprise Scaled Score 0.78 0.76Enterprise Rasch Score 0.78 0.80STAR Early LiteracyTechnical Manual89