Adam M. Enders

Introductory Material

• MORALS Optimal Scaling code

• MORALS Optimal Scaling data

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Classical Test Theory, the Summated Rating Model, and Reliability​

• SRM and Reliability code

• SRM and Reliability data

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(Unidimensional) Item Response Theory

• Mokken Scale Analysis code

• Mokken Scale Analysis data

• Suspicion 2014 CCES data

• Parametric IRT code

• DIF code

• DIF data

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(Unidimensional) Unfolding

• Unfolding code

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Singular Value Decomposition, Biplot, and PCA

• SVD and Biplot code 1

• SVD and Biplot code 2

• Political Sophistication data

• Banks' (2005) data

• PCA code

• Categorical (Nonlinear) PCA code

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Factor Analysis

• Factor Analysis code

• Factor Analysis "by hand" code

• Group Feeling Thermometer data

• FA "SCOTUS legitimacy" example

• Legitimacy data

• Nonlinear EFA code

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Multidimensional Scaling and Extensions

• Classical MDS and MDS "by hand" code

• Metric and Nonmetric MDS via smacof code

• Country Similarities data

• 2004 ANES Thermometer data

• Interpreting MDS Solutions code

• Degenerate Solutions and Correlations as Input code

• WMDS code

• Vector unfolding model code

• Vector model data

• Multidimensional unfolding code

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Correspondence Analysis

• CA "by hand" code

• CA and MCA code

• MCA (vote choice) data

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