reliability analysis

1. Can the reliability be used using Cronbach's alpha when the base of the respondent for each question is different?

For example, in the survey on job satisfaction, questions A1 to A10 consist of items related to work-life balance. At this time, the survey was conducted for all respondents in A1~A5, only white-collar in A6~A8, and only blue-collar in A9~A10. At this time, is it not unreasonable to measure the...
2. Reliability Test - Cronbach

Hello, Through my quasi-experiment in math classroom, I have made pre and post-exams. Each exam had 3-4 open-ended questions (not MCQ). Each question had a different score. Each exam is summed up over 10. I was asked to do the reliability test using spss for each exam. The question is, should...
3. Is cronbach alpha applicable ?

Recently, I'm doing a pilot study for my questionnaires however I got 0.05 for my cronbach alpha. My questionnaires consist of two part : 1. Demographical parts ( also include things like likert scale) 2. BDI inventory ( Beck Depression Inventory) The problem is the result of SPSS told me...
4. A change in process is proposed. How do I determine if the change will be good without any data?

I am working on a project where a machine has a part replaced every 500 hours it's been run or it fails (which ever comes first). I have been asked to determine if we should lower the replacement time to 100 hours to make the machine have better reliability. I have a lot of data of failures of...
5. Reliability Analysis for Ability Test (Signal Detection)

Good day all, I have been tasked with working out the alpha for an ability test which measures only two factors: Median Reaction Time (in ms) and Score based on how many signals were detected (value out of 40). My question is how do I go about doing this? Previously I've computed the...
6. inter and intra rater reliability

I am doing a reliability study during which we had 2 individuals take 6 different measurements using a custom tool. Each of the 6 measurements was repeated 10 times. Now I would like to see if each person was consistent time after time (10 trials) among each of the 6 measures. I would also like...
7. Reliability in health and disease (ICC,CoV) - Separtely or combined

I am currently writing an article. However, I have a concern regarding my statistics part. I calculated the ICC (Intraclass correlation) and CoV (Coefficient of Variation) over the group of healthy subjects and over the diseased subjects (measurement within two weeks) and they both are good to...
8. Standard error of measurement (SEM) consistency - what's the formula?

Hello, everyone How to calculate the standard error of measurement (SEM) but for consistency? I would like to find the formula and the paper which describes it. As it is for SEM consistency, it is not equal to SD divided by the √number of observations of a sample. Could someone help me...
9. Problem with the reliability analysis and factor analysis.

Hi, As I am working on the statistical research for my graduation, I encountered two problems; 1) I am measuring two multi-dimensional concepts, and I used a factor analysis to measure the components. One of these concepts turned out to consist of 6 components. I regrouped all items...
10. Negative Cronbach’s Alpha When Running a Reliability Analysis

Hi Talk Stats member. I have a question about getting a negative Cronbach’s Alpha when running a reliability analysis in SPSS. Here is what I have: I have a standardized exam taken by 19 participants/valid cases. The exam was graded with the score range of 1 - 4, including the decimals...