1
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1answer
33 views

Correlations within Factor in a psychometric measurement instrument

I am working with results of a psychometric test. There are twelve factors and each have three subfactors. My problem is that one of the subfactors correlates very highly 0.3 to 0.7 with subfactors of ...
0
votes
0answers
14 views

theoretical profile correlation

My data (n > 4000) contains the results of two separate tests (instruments). I have a profile made from likert scales for one of the instruments (S1, S2, ... S20). I want to find the corresponding ...
0
votes
1answer
76 views

Several items for one construct

I am a dummy in statistics but need to accomplish some simple survey analyses. My question is: if I have several questions (items) for one construct (say, questions JS1-JS3 for job satisfaction) with ...
1
vote
0answers
78 views

how to analyze necessary/sufficient relationship?

Good day! I'm a second year psych grad student. From my fascination with formal logic, I wondered (just personal; not homework) about how to statistically establish necessary/sufficient ...
1
vote
2answers
415 views

What factors do I have to consider when deciding if creating a composite score using four t-scores is defensible psychometrically?

Edit: I've conducted an item analysis on four variables - two quizzes and two psychological attributes, namely emotional intelligence and happiness. Its a within-subject design with students as ...
2
votes
1answer
71 views

Ordinal reliability for small examinee population

Biswas considers "a classical-type linear model of observed score ($X$), true score ($T$), and random error ($E$)" and asserts ... in test theory, interpretation of $\rho_{TX}$ has an intuitive ...
1
vote
2answers
384 views

Rules of thumb for creating composite scales

Normally when I create an index I basically just take the or averages of the individual variables that comprise the index. But I'm wondering if one should / could not, take the product? E.g., a scale ...
7
votes
4answers
9k views

How to compute correlation between/within groups of variables?

I have a matrix of 1000 observations and 50 variables each measured on a 5-point scale. These variables are organized into groups, but there aren't an equal number of variables in each group. I'd ...
6
votes
3answers
1k views

Validating an existing questionnaire into another language

I am doing research and trying to use a questionnaire that is available in English in another language. Is there a systematic approach for validating a questionnaire in another language? What ...
6
votes
2answers
1k views

Item Analysis for an R newbie

I am trying to assess a 20-item multliple choice test. I want to perform an item analysis such as can be found in this example. So for each question I want the P-value and the correlation with the ...
6
votes
3answers
3k views

Differences between tetrachoric and Pearson correlation

Currently I'm analysing around 300 items in the field of education. I'm interested in the dimensionality of the dataset. So I compute a matrix of tetrachoric correlation. The goal is to do a factor ...