Technical Manual - Renaissance Learning

ValidityThe Validity of Early Numeracy Test Items as Measures of the Early Literacy Constructbetween the EL17 scores and the EN5 scores was .64 which was greater than thatbetween the EL5 scores and the EN5 scores (r = .59).Table 43: Score Correlations (N = 6,438)EL17 1EL17 EL5 EN5 Service RatingEL5 0.73* 1EN5 0.64* 0.59* 1Service 0.77* 0.69* 0.61* 1Rating 0.50* 0.47* 0.43* 0.52* 1Note: * indicates significance with p-value < 0.0001.Often, correlations do not tell the whole story. Next, we present the results of thefactor analysis that examined the relationship of the 5 variables to the underlyingconstruct. Factor analysis can identify as many as 4 distinct latent attributes(factors) that account for the intercorrelations among 5 variables. One standardpractice is to disregard any factors that have an eigenvalue less than 1.0; usingthat criterion in this case resulted in retaining only one factor. Several variants offactor analysis were applied and they all resulted in one factor. The factor loadingsare shown in Table 44. All the scores strongly loaded on the one dominant factor,which is an indication that the EL and the EN items both measure the sameunderlying construct. The factor represents the construct of interest whereas theloadings represent the correlation between the scores on each variable (e.g., EN5)and the construct.Table 44:Factor LoadingsVariableFactor LoadingEL17 0.89EL5 0.81EN5 0.72Service 0.86Rating 0.58The scree plot of the extracted factors is presented in Figure 12, which provides avisual confirmation that there is only one dominant factor. The empirical evidencestrongly suggests one dominant factor representing the construct of interest. TheEN items demonstrably measure the same construct as do SEL “Service” and theEL items within SEL Enterprise. This supports including the EN items in thecalculation of SEL Enterprise scores.STAR Early LiteracyTechnical Manual94