1. A

    RMSEA impacted by high reliability scores..

    Hello again Sorry - In relation to running Confirmatory Factor Analysis - I'm wondering whether someone is aware of RMSEA being impacted by high reliability scores ? As background, I understand that RMSEA can be affected by high factor loadings. Currently, I have a construct with 6...
  2. A

    Composite reliability vs Cronbach's alpha

    Hello Wondering if someone could clarify I'm developing a new measure with 10 constructs. Each construct has between 4 - 6 items. I've been assessing the reliability for each construct using both Cronbach's alpha and composite reliability scores. For most constructs, both...
  3. B

    Interrater Reliability. Is MORE better?

    Which design is more powerful: testing interrater reliability with 2 judges or 4 judges? (citations appreciated)
  4. M

    How to calculate inter-observer/ inter-rater reliability of ordinal data in R?

    Hello, I have the question which measurement to use in order to calculate the inter-observer reliability in R once for an ordinal and once for a nominal data set. Part1) Ordinal data set 2 observers gave scores on a scale from 1.0 to 5.0 with steps of 0.25 Example of data: observ1...
  5. I

    Parameter estimation

    I am doing project in which I need to estimate weibull parameters for car part failures ( I know data follows weibull ). I have 1000 cars data (part failure data). Now the problem is suppose some part fails after 6 year( from date of manufacturing) . But i have data of only first three year. Now...
  6. S

    reliable change index and reliability coefficient

    Hi. I'm a bit embarrassed at my inability to figure this out even with the vast amounts of information available to me via the internet. Any help is appreciated. (Feel free to make fun of me too.) I am trying to calculate RCI (reliable change index) which I am able to do with a simple formula...
  7. W

    accounting for volunteers giving a survey

    When writing about validity/ reliability, how do I take into account volunteers who have given the treatment to the participants rather than myself (the researcher)?
  8. E

    How to calculate test reliability with different exam versions

    Hello All, I'm new to this forum and this is my first questions. We have 1500 students and each student will receive a test that has 30 question. We have a test bank that has 763 questions. The test for each student will be different (i.e. different version with different 30...
  9. J

    Utilizing Individual Data Points in an ANOVA, Reliability, Replication

    Hi all. Suppose you are conducting a study with n=10 subjects. Each subject runs through a behavioural experiment for treatment A and treatment B, and several data points are collected. Before conducting the ANOVA, an AVERAGE score is calculated for each subject based on all their...
  10. B

    Estimating sample size for reliability study

    Hello, I'm having problems calculating the required sample size for my PhD study. I have designed my first study, which is comparing moral reasoning abilities in people with a brain injury to a healthy comparison group. I have used previous similar research and G Power to estimate the...
  11. B

    Help with inter-rater reliability

    Hi all, I've got a set of data that I need some advice on. I'm working on a pilot project where a group of four people evaluate essays. The way that I'm working it is that each essay is read by two of the four people on the assessment team. Each of these individuals will rate five different...
  12. W

    Correlation of Leading & Lagging Indicators

    Greetings. I am working on a organizational performance dashboard for my company. I have identified lagging and leading indicators in five domains of the organization that are critical to ongoing success of the firm. These indicators are essentially organizational metrics. I want to...
  13. R


    How do I calculate reliability for something that I do not have an "exact" answer for? For example, in an observational setting with 2 observers counting the number of times eye contact is given for 2 different participants (total of 4 observances). There is no absolute answer for eye contact...
  14. B

    Minimum sample size for calculation of guttamns lower bounds?

    Minimum sample size for calculation of Guttmans lower bounds? Hi there, I am in the process of assessing the internal consistency of two tests, test A & B. Both tests are measuring the same thing so I am also conducting a split half reliability analysis. All participants have taken both...
  15. H

    Interrater Reliability of Dichotomous Variables

    Disclaimer: Not psychological research, I know, but the type of statistics are more often used in psychology than in medicine, so I'm asking for help here. Background: I had 4 radiologists read CT scans of ~50 patients to assess whether a series of 'signs' were present or not. After a washout...
  16. G


    I was wondering what methods you can use if you are trying to predict failure in a product. I have a product and the following information about the product: 1. The date it was produced 2. number of products produced in the lot 3. The number of products purchased out of that lot 4...
  17. G

    Life Data Analysis

    Good Morning, This is the first time that I have posted anything and I am really in need of guidance. I am trying to figure out the best way to predict failure using warranty data. I have a product that had very few claims in the beginning, but the longer the life of the product the...
  18. H

    Intra- and Interrater reliability of imaging findings

    Hi everyone, I'm having some difficulty deciding how best to analyze the data from a project. I had 4 radiologist read CT scans looking for specific signs (mostly giving True/False answers) on two occasions separated by a washout period. The last two variables included a 'Questionable'...