Psychometrics has evolved as a subfield of psychology to become the science of measurement of unobservable individual characteristics.
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2answers
87 views
Error message from grm() in ltm: subscript out of bounds
I am analyzing a survey data set. One of the items in the survey is:
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1answer
77 views
Sampling considerations in psychometric applications of item response theory
Background
I have developed a recent interest in Item Response Theory and its applications. I am studying clinical psychology and am most interested in polytomous models aimed at modelling ...
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1answer
242 views
Predicting dependent variables where independent variables are samples with differing sample size
Is there a standard method of dealing with independent variables, where they are samples from a known distribution, and the sample sizes differ from sample to sample?
I'll give an example of what I ...
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1answer
691 views
Likert scale and yes/no calculation of one score
My survey is based on observations and interviews. The observation questions are yes/no type questions and interview questions are 4 points.
1 = never, 2 = sometimes, 3 = usually, and 4 = ...
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0answers
97 views
Are discrimination parameters in two-parameter IRT models only specific to items?
Discrimination parameters in two-parameter model from IRT are usually considered item parameters.
But I've come to doubt it.
Think about psychophysics; for example, detecting luminance.
I don't ...
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0answers
72 views
Testing graded response model thresholds for significance?
I have a data set in which two raters have each rated N samples using a 5-point ordinal rating scale. My primary interest is in whether these two raters make significantly different use of those ...
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0answers
164 views
Dealing with poor fit in an Item Response Theory model
I'm studying an online course with about 3000 students who each took several quizzes and I'm trying to apply Item Response Theory (using the ltm package in R) to model the questions, determine which ...
2
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0answers
208 views
Maximizing Cronbach alpha to select the number of variables that define a given construct
I can't seem to find this anywhere on the internet or in my books. I'm putting together a construct for an underlying variable.
Is it acceptable to have a construct with two variables if that ...
2
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0answers
227 views
Fixing error variance in a path analysis to model measurement error in scales using sem package
I want to construct a path analysis model that can account for measurement error in totally aggregated parcels, which refer to parcels where all of the items in a scale are summed or averaged. If I am ...
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0answers
1k views
How to carry out a Likert scale analysis?
Context:
My research aims to assess whether parents who have been involved in a relationship with a social worker are at higher risk of child abuse/neglect.
I am trying to establish whether there ...
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0answers
35 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 ...
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0answers
22 views
What coefficient could I use to calculate the relative difficulty of a test in relation to others using only mean and population standard deviation?
I have a series of tests, all of them of different difficulty, and from each of them I get an average score and a population standard deviation; e.g:
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0answers
181 views
Which correlation analysis is appropriate for binary and ordinal variables?
Violin players were asked to rate 5 violins from least to most rich on a [0 1], 0.05-increment scale, ...
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0answers
40 views
Omega H asymptotic
In the omega function in the psych package for R, we have several outputs including Hierarchical omega, Asymptotic omega and Total omega.
I was reading about the outputs, but I find nothing about ...
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0answers
254 views
How to validate a survey when using Likert scale?
I have developed a very simple survey to measure the attitudes of students toward science fairs. It makes use of the Likert Scale and Open Ended Questions. Do you have a recommendation for the type ...
1
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0answers
149 views
Obtaining factor scores from a factor analysis of mixed types (both ordinal and scale) variables
I have to analyze a data set having both ordinal and scale variables. What I was trying to do was to factor analyze the data. The data was in SPSS. But I think SPSS factor analyzes the data by ...
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0answers
173 views
How is the proof that the Quartimax/Varimax-rotation converges?
Empirically the quartimax-/varimax-rotation has proven useful and it was always converging in my applications. But from my readings years ago I have a vague remembering, that the fact of a proof of ...
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0answers
162 views
Survey Data - Factor Analysis
I was hoping you could help with this question. I have a survey, a 30-item instrument. I've got 18 responses back from this.
I also have a paper in which they've done a principal axis factor ...
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0answers
265 views
Using Rasch model to explain relationships between a set of dependent and independent variables
My research study is in development economics. My data consist of more than one independent variables (continuous and categorical) as well as more than one dependent variables (categorical 5-point ...
