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Sweating the Small Stuff: Does data cleaning and testing ... - Frontiers

Sweating the Small Stuff: Does data cleaning and testing ... - Frontiers

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Kasper <strong>and</strong> ÜnlüAssumptions of factor analytic approachesTable 5 | Number of extracted dimensions for <strong>the</strong> PIRLS 2006 testbooklet number 4, German sample.Table 7 | Loading matrix for four factors principal axis analysis of <strong>the</strong>PIRLS 2006 <strong>data</strong> for test booklet number 4, German sample.Extraction methodFactor modelItemFactorPCA a EFA b PAA c1 2 3 4Kaiser–Guttman criterion 6 6 6Scree test 1 1 1Parallel analysis method 1 4 4aPCA, principal component analysis; b EFA, exploratory factor analysis; c PAA,principal axis analysis.Table 6 | Loading matrix for four factors exploratory factor analysis of<strong>the</strong> PIRLS 2006 <strong>data</strong> for test booklet number 4, German sample.ItemFactor1 2 3 4R011A01C A,R 0.15 0.26 0.39 −0.05R011A02M A,R 0.14 0.28 0.34 0.19R011A03C A,R 0.16 0.24 0.09 0.03R011A04C A,I 0.39 0.19 0.10 0.06R011A05M A,R 0.22 0.08 0.19 0.21R011A06M A,R 0.20 0.03 0.14 0.06R011A07C A,R 0.50 0.20 0.22 0.15R011A08C A,R 0.35 0.04 0.38 −0.09R011A09C A,I 0.55 0.18 0.11 0.00R011A10M A,I 0.28 0.27 0.22 0.11R011A11C A,I 0.37 0.06 0.14 0.02R021E01M L,R 0.08 0.45 0.19 −0.06R021E02M L,R 0.02 0.49 0.09 0.24R021E03M L,R 0.14 0.34 −0.02 0.02R021E04M L,R 0.17 0.28 0.15 0.02R021E05C L,R 0.22 0.23 0.32 0.12R021E06M L,R 0.17 0.44 0.09 0.28R021E07C L,I 0.13 0.06 0.48 0.22R021E08M L,I 0.32 0.23 0.04 0.48R021E09C L,I 0.45 0.24 0.02 0.20R021E10C L,I 0.27 0.23 0.17 0.07R021E11M L,I 0.00 0.01 0.06 0.40R021E12C L,I 0.38 0.17 0.31 0.22Factor loadings greater or equal 0.30 are highlighted.A, Acquire <strong>and</strong> Use Information; L, Literary Experience; R, Retrieving <strong>and</strong>Straightforward Inferencing; I, Interpreting, Integrating, <strong>and</strong> Evaluating.7.2. OUTLOOKWe have discussed possible implications of <strong>the</strong> findings forcriterion-referenced tests <strong>and</strong> large scale educational assessment.The assumptions of <strong>the</strong> classical factor models have been seento be crucial in <strong>the</strong>se application fields. We suggest, for instance,that <strong>the</strong> presented classical procedures should not be used, unlesswith special caution if at all, to examine <strong>the</strong> factorial structure ofdichotomously scored criterion-referenced tests. Instead, if modelviolations of <strong>the</strong> “sensitive” type are present, better suited or moresophisticated latent variable models can be used (see Skrondal <strong>and</strong>R011A01C A,R 0.15 0.26 0.40 −0.06R011A02M A,R 0.14 0.29 0.33 0.18R011A03C A,R 0.16 0.24 0.09 0.02R011A04C A,I 0.38 0.20 0.10 0.06R011A05M A,R 0.22 0.07 0.19 0.24R011A06M A,R 0.19 0.02 0.14 0.07R011A07C A,R 0.50 0.20 0.22 0.16R011A08C A,R 0.36 0.03 0.38 −0.08R011A09C A,I 0.54 0.19 0.12 0.00R011A10M A,I 0.28 0.27 0.22 0.11R011A11C A,I 0.38 0.07 0.13 0.02R021E01M L,R 0.07 0.45 0.19 −0.06R021E02M L,R 0.03 0.49 0.09 0.24R021E03M L,R 0.14 0.33 −0.02 0.02R021E04M L,R 0.17 0.26 0.16 0.04R021E05C L,R 0.21 0.23 0.32 0.12R021E06M L,R 0.17 0.44 0.08 0.27R021E07C L,I 0.13 0.06 0.47 0.23R021E08M L,I 0.32 0.24 0.05 0.46R021E09C L,I 0.45 0.24 0.02 0.19R021E10C L,I 0.27 0.24 0.17 0.06R021E11M L,I 0.00 0.02 0.05 0.40R021E12C L,I 0.38 0.17 0.30 0.22Factor loadings greater or equal 0.30 are highlighted.A, Acquire <strong>and</strong> Use Information; L, Literary Experience; R, Retrieving <strong>and</strong>Straightforward Inferencing; I: Interpreting, Integrating, <strong>and</strong> Evaluating.Rabe-Hesketh, 2004). Examples are item response <strong>the</strong>ory parametricor non-parametric models for categorical response <strong>data</strong> (e.g.,van der Linden <strong>and</strong> Hambleton, 1997). Fur<strong>the</strong>rmore, we wouldlike to mention item response based factor analysis approaches byBock <strong>and</strong> Lieberman (1970) or Christoffersson (1975, 1977). Wemay also pay attention to tetrachoric or polychoric based structuralequation models by Muthén (1978, 1983, 1984) <strong>and</strong> Muthén<strong>and</strong> Christoffersson (1981).As with factor analysis a general problem (e.g., Maraun, 1996),we had to deal with <strong>the</strong> issue of rotational indeterminacy <strong>and</strong>of selecting a specific rotation. We have decided to use varimaxrotation, due to <strong>the</strong> fact that this rotation is most frequently usedin empirical educational studies (for better interpretability of <strong>the</strong>factors). Future research may cover o<strong>the</strong>r rotations (e.g., quartimaxor equimax) or <strong>the</strong> evaluation of parameter estimation byexamining <strong>the</strong> communality estimates for each item (which arenot dependent on rotation, but are a function of <strong>the</strong> factor loadings).Moreover, <strong>the</strong> orthogonal factor model may not be realistic,as factors are correlated in general. However, in <strong>the</strong> current study,it may be unlikely that having non-zero population factor loadingsfor correlated dimensions would substantially affect <strong>the</strong> findings.In fur<strong>the</strong>r research, we will have to study <strong>the</strong> case of <strong>the</strong> oblique(non-orthogonal) factor model.<strong>Frontiers</strong> in Psychology | Quantitative Psychology <strong>and</strong> Measurement March 2013 | Volume 4 | Article 109 | 139

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