Tomasz Rak

8 Questions 65 Answers 0 Followers

Questions related from Tomasz Rak

Why is the confirmatory model (CFA) with master latents unidentified?

I wanted to perform a confirmatory analysis on Schwartz PVQ questionnaire part. The construction of the questionnaire assumes that individual items combine into dimensions (latent variables),...

15 January 2021 2,142 9 View

Is there any interaction equivalent of Cochran's Q test (like 2x3 design)?

I have data on the effectiveness of the three treatments: T1, T2 and T3 for each patient. Each variable is coded dichotomously - 0 = drug not working; 1 = drug is working. The patient could feel...

01 December 2020 1,305 14 View

Are we methodologically allowed to divide DCE question-set into research subgroups?

Introduction: the DCE method is used to measure the preferences of a set of (mainly) nominal features that make the research plan in the form of scenarios that are a combination of these features....

12 February 2020 8,356 7 View

How to group many same correlations in subgroups into similar subgroups by coefficient?

I have a correlation between two variables, and 40 groups in which I would like to compare it. Then extract several larger groups (reduce the number of subgroups) in which the correlations are...

06 September 2019 1,837 5 View

Non-equal variances t-test in SPSS - it's Welch or Cochran-Cox?

Can anyone help me answer the question of whether t test for unequal variances is calculated in SPSS according to Welch or Cochran-Cox correction? Test statistics are the same, they differ only...

30 May 2019 7,609 14 View

Is there any reason why one can not reduce dimensions with PCA/Alpha before putting them into SEM model?

Suppose I have three measurable variables (A, B, C on figure below) and one latent (L) in my SEM model. This one latent one is a construct/dimension consisting of 5 questions from some...

08 April 2019 1,038 6 View

Statistical Power (observed) standard symbol in APA/Harvard?

If I have to report the observed statistical power, what is its standard symbol in tables and text? 1-b? Are there any guidelines in the APA or Harvard standards?

18 September 2018 1,772 17 View

In APA style should we report degrees of freedom for Spearman's rank correlation?

In APA 6.0 manual there is information (pp 113) about reporting degrees of freedom for Pearson correlation coefficient - and for parametric correlation it is sugested to report df's. But what...

04 April 2017 5,422 2 View