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Date	Topic	Video	Material
2016-10-17	Introduction and Outline of the lecture Repetition of the basic ideas of Classical Test Theory (CTT) Models of CTT The model of essentially tau-equivalent variables	Video (Stream)	Slides (Organizational Issues & Repeating the Essentials of Classical Test Theory) Slides (Model of essentially tau-equivalent tests) Blackboard sketches
2016-10-24	The model of essentially tau-equivalent variables (continued) The role of latent variables in Psychology The logit transformation of probabilities The definition of the latent variable in the Rasch model Rasch homogeneity U-Conditional independence of the items An example with Joe and Ann illustrating the Rasch model	Video (Stream)	Slides
2016-11-07	Rabix, a program for explorating the Rasch model and the Birnbaum model Itemcharacteristic functions Likelihood functions Estimation of the person parameter using maximum likelihood Item information functions Test information function Standard error function for the estimation of the person parameter Identification of the item parameters	Video (Stream)	Slides Rabix Blackboard sketch 01 Blackboard sketch 02
2016-11-14	The life-satisfaction data Recoding of the negatively formulated items Analysis of the life-satisfaction data with the Rasch modell (WINMIRA) Person parameter estimation Item parameter estimation	Video (Stream)	Material
2016-11-21	Interpretation of the Q-statistics in Winmira for the items Bootstrap model test Generating data according to the Rasch modell Analysis of the generated data with Winmira Generating data according to the Birnbaum model Analysis of the generated data with Winmira, in particular the Q-statistics and bootstrap procedure Generating data according to the Birnbaum model according to a latent variable model with two latent variables Analysis of the generated data with Winmira	Video (Stream)	Material Blackboard sketch 01 Blackboard sketch 02
2016-11-28	Summary presentation of the Birnbaum 2-PL-model Summary presentation of the Birnbaum 3-PL-model (with guessing parameter) Analysis of the life satisfaction scale according to the Rasch model with Mplus Discussion of the Mplus Input and Output for this model	Video (Stream)	Slides (The two parameter logistic Birnbaum model) Slides (The three parameter logistic Birnbaum model) Mplus-In- and Outputs Blackboard sketch 01 Blackboard sketch 02
2016-12-05	Specification of the 2PL-Birnbaum model in Mplus for the life satisfaction data Test of the hypothesis: „The Rasch model holds“ using the Wald test Specification of the 2PL-Birnbaum model in Mplus for generated data that follow the Birnbaum model. Test of the hypothesis: „The Rasch model holds“ using the Wald test for these data that follow the Birnbaum model	Video (Stream)	Material Blackboard sketch
2016-12-12	A first two-dimensional IRT model with an own latent variable for the positively and for the negatively formulated items. A first alternative to the Birnbaum model Testing the hypothesis: The correlation between the two latent variables is 1. The general structural model for the latent variables and the matrices involved in this model. An alternative way of testing the hypothesis mentioned above. The regression of Xi2 on Xi1 is perfect. (The variance of the residual is 0).	Video (Stream)	Material Blackboard sketches
2016-12-19	Rasch and Birnbaum analog probit models Model test in these models A two-dimensional probit model Data generation according to the Birnbaum analog probit model	Video (Stream)	Material Blackboard sketches
2017-01-02	Link functions and response functions in the logit model and in the probit model Assumptions defining the logit model and the probit model Factor analytic representation of the probit model Relationships between the parameters of different models and parameterizations Analysis of the probit model using generated data First ideas of item response latent state-trait theory	Video (Stream)	Slides Mplus-In- and Outputs Blackboard sketch 01 Blackboard sketch 02
2017-01-09	Basic ideas of latent state-trait-theory Singletrait model, multistate model and multistate-singletrait model Analysis of a probit multistate model with the life-satisfaction scale (3 times points) Analysis of this model with the additional constraint: The correlations of the three latent state variables are equal to 1 Analysis of a probit singletrait model with the life-satisfaction scale (3 times points) Differences between the last two models	Video (Stream)	Mplus-In- and Outputs Blackboard sketches
2017-01-16	The Partial Credit Model U-conditional threshold-probabilities The two assumptions defining the Partial Credit Model and the definition of the latent variable Interpretation of the threshold parameters Graphs of the U-conditional threshold-probabilities for different categories as a function of the latent variable Graphs of the U-conditional probabilities for different categories as a function of the latent variable Ways of fixing the (version of the) latent variable Using the Partial Credit Model for four items of the scale „well-being“ of the Multidimensional Mood State Questionnaire with Winmira. Interpretation of the output of Winmira	Video (Stream)	Winmira-Outputs Blackboard sketch
2017-01-23	Graded Response Model (GRM) with logit and probit link functions Basic assumptions and their implications for the category probabilities Thresholds and discrimination parameters in these models Application of the probit GRM for the data of the well-being scale of the MDMQ at time 1 Fixing the scale of the latent variables Generalizing the probit GRM to a latent state model for three time points	Video (Stream)	Slides (updated 2017-01-27) Mplus-In- and Outputs Blackboard sketch 01 Blackboard sketch 02
2017-01-30		Video (Stream)	Slides Blackboard sketch