scale development

  1. F

    Factor Analysis Question

    I am currently working on constructing a scale. The questions on the scale are measured on a scale from 0-100 in increments of 10, similar to the DES. I ran a factor analysis with my pool of items and eventually got to a scale I liked the psychometrics of. At this point, I realized I didn't...
  2. F

    Factor Analysis newbie seeks your help

    Hi, Perhaps unwisely as a newcomer to stats, I have taken on a scale validation project. I’ve searched the literature and can’t find anything so this is the issue: I’m developing a scale that (hypothetically) will identify, differentiate and measure two different constructs occurring in...
  3. U

    Likert Scale - Not Applicable Option

    I have the following scales: 1 (Strongly Disagree); 2 (Disagree); 3 (Not Applicable); 4 (Agree); 5 (Strongly Agree); Questionnaire responses: Question Item1: 2; Question Item2: 3; Question Item3: 1; Question Item4: 1; Question Item5: 4; If I need to average the above responses...
  4. Martin Marko

    A thought about the link between Revelle's β coeff and CFA. Related?

    Hi stat freaks! :confused: I've just conducted an analysis of a scale's consistency (coeffs alpha, beta, omega, theta) and CFA to inspect the scale. I was wondering about the relation between Revelle's beta coeff. and CFA results. Beta coef. = estimates the worst possible split half of a item...
  5. S

    [LISREL 8.7] syntax for a formative second order model

    Hi: I am developing a scale, which is theoretically a first order reflective, and second order formative model. I have already analyzed the first order model and everything's ok, and results indicate that i should continue with a second order formative model. I do not know how to write the...
  6. E

    How to calculate max/min scales on a scatter plot

    Good morning! I have 3 log scatter plots that I want to establish smooth maximum and minimum lines. What is the usual mathematical method to do that? (Image and excel file links below.) The black lines on the scatter plot images are hand drawn. The third scatter plot is especially tricky...
  7. D

    Cronbach Alpha for 3-item scale

    I've read that cronbach alphas are also dependent on the number of items, and for a scale meant only for descriptive purposes, what is the acceptable alpha for a 3-item scale? Would, say, .45 suffice?
  8. G

    Calculating Item Discrimination Index for a Likert Questionnaire

    I am currently in the early stages of developing a scale that measures prejudicial attitudes. I have just run a pilot study with the first draft of the questionnaire, and I am now in the process of trying to narrow it down to a smaller number of questions. Right now, I am trying to do item...
  9. J

    Create scale (or index) using items that are measured on with different scales

    Hello, I would like to make a scale of several items that are theoretically related, have a >.8 cronbach's alpha, but were measured on different scales themselves. Also, each factor has a different number of items. So, questions 1~3 measured by 1 = very small ~ 5 = very large questions...
  10. L

    Scale validity testing (concurrent)

    Hello I need to test the validity of a scale we have created. We have another pre-validated scale to compare with for a concurrent validity test. We are asking people to complete both question sets and then intend to correlate their responses but am not sure how exactly to go about this...
  11. F

    How to combine single Likert items into one scale? (Time-sensitiv)

    Hello, I have a very time-sensitive question: I am replicating a theory that uses 12 Likert items to measure three latent variables (4 items per latent variable). Also in my study I use these 12 likert items that measure three latent variables. Every latent variables is measured by 4...
  12. D

    Psychometrics with small datasets?

    Hi, I am developing a new measurement scale for cannabis withdrawal, but only have 50 people in my dataset (they filled the scale in every day for 3 weeks - 1 week was a baseline smoking as usual phase, the other two were abstinence from cannabis). I want to do a full psychometric...