spss

  1. L

    SPSS Regression - Independent Variable excluded

    Hello, I was running a linear multiple regression as well as a logistic multiple regression in SPSS. After that when looking at the results, I realised that in each regression, one independent variable was automatically excluded by SPSS. Did we do something wrong here or what do we have to do...
  2. M

    Comparing correlation coefficients

    Hello, I have a large sample of patients who have had a TIA, minor stroke or major stroke. I have been looking at correlations in each of these three groups. Is there a statistical test in SPSS (or elsewhere) that would allow me to compare the correlation coefficients between each of three...
  3. T

    Help with stats work

    Hi everyone at Talk Stats, I've really been struggling on the correct method to use to prove/disprove if my results are statistically significant. For the context in 2006/07, the UK tuition fees have changed from £1k to £3k and then again in 2012 to £9k. Attached is a text file of my collected...
  4. F

    Cox regression results interpretation

    Hi! I am currently working on a statistical analysis on a prospective cohort population. We are looking at a specific protein concentration at baseline and relate this to a certain outcome. The outcome group have been matched with twice as many control individuals from the same cohort. The...
  5. F

    Determining significant difference in mean ratings between two products

    Hi all, I have gathered 180 respondents and asked them to rate two products (so each respondents rates both products). The only difference between the two products is that one product has an extra feature and the other does not. Now I want to know whether there are significant differences...
  6. J

    HELP! SPSS - Independent T- test - t cannot be computed because at least one of the groups is empty

    Hello, I have a question regarding the independent t-test in SPSS. I already run a frequency test which does not show any data missing. What can I do to find the mistake? I want to analyze if there is a difference between the answers of the male and female population. Help is very much...
  7. S

    N changes when weighting cases in SPSS

    Hello! I'm stuck here while analyzing data in SPSS and I could really use some help. I'm weighting cases in my dataset, but when I run any analysis the N in the output has changed from 189 to 176. This puzzles me, each case has a weighted value when I check my dataset. Where do I go wrong? This...
  8. S

    What test to use in SPSS....PLS HELP :((

    Hi, I'm trying to write my dissertation for my 3rd year undergrad project and I am really stuck with the stats :( I carried out an observational study using questionnaires looking at public knowledge of dementia. I specifically want to look at how knowledge of Alzheimer's Disease (AD) and...
  9. G

    Which stats test should I use?

    I am using SPSS to analyse data. I would like to know whether there is a correlation between age and having diabetes (categorical - Yes/No). What is the most appropriate test to use for this???
  10. O

    Choice of test

    Hi all, I'm currently inputting the results for my dissertation on 'the effects of caffeine ingestion on repeated sprint performance post-fatigue'. My dependent variable is sprint time (7 x 30 m sprints) and my independent variable is the condition (control, caffeine and placebo). I have already...
  11. J

    Proportion Z-score calculator

    Hi! I have a sample (of 30) who’s outcome was measured binomially as either YES/NO. The expected population should have entirely NO answers. I therefore want to calculate if there is a significant difference in the proportions between sample of 23/30 (23-YES, 7-NO) and the expected proportion of...
  12. A

    What stats tests should I be running?

    I have data looking at the number of different prey species and the number of different predator species that visited a waterhole and I'm categorizing by time, so eg. 3-6am : 5 prey, 2 predator 6-9am: 10 prey, 1 predator ect. I've tried doing a 2 way anova, and chi squared test but I dont...
  13. C

    Why is there a difference in the confidence intervals calculated by SPSS compared to SAS and Epi-Info 7?

    I writing sample code for colleagues in developing countries who will use it to analyze a multi-stage, cluster-sample survey that measures the prevalence of infection with soil-transmitted intestinal worms. So far, I have used three of the software packages they might use: IBM SPSS Statistics (I...
  14. A

    What Stats should I do?

    I have data looking at the number of different prey species and the number of different predator species that visited a waterhole and I'm categorizing by time, so eg. 3-6am : 5 prey, 2 predator 6-9am: 10 prey, 1 predator ect. I've tried doing a 2 way anova, and chi squared test but I dont...
  15. L

    Ordinal logistic regression - how to calculate odds ratio?

    I am running ordinal logistic regression in SPSS. I would like to calculate odds ratios. What do I need to add to the syntax to obtain odds ratios? Currently my syntax looks like this: PLUM druguse WITH age yrsill BY Any_MH group /CRITERIA = CIN(95) DELTA(0) LCONVERGE(0) MXITER(100) MXSTEP(5)...
  16. M

    One sample or independent samples t-test?

    Hello everyone :) I have a problem with a mark I have received regarding my stats assignment. The data was comparing management scores (scale variable) between countries (nominal variable with 7 categories) One of the tasks was to "Test the null hypothesis that there are no significant...
  17. P

    Geisser-Greenhouse Correction Nonsignificant Effect

    I've read several pieces of documentation that say that the Geisser-Greenhouse correction for sphericity always increases the p value. I've noticed in SPSS that if a test is not significant (before any correction), sometimes the Geisser-Greenhouse corrected value is actually less than the...
  18. A

    3 way ANOVA following it up

    This is quite simple question but im more simple :p I have DV and 3 IVs, each 2 levs. Making up example, lets say they are: DV=performance%, IV1=trial type (seeing, hearing) IV2=item type (target, distractor) IV3=confidence (high, low) Subjected to a 2x2x2 RM ANOVA in SPSS and i see no 3 way...
  19. S

    Constant not sig. in multiple regression - does it matter?

    I did a hierarchical multiple linear regression in SPSS with three predictor variables. All the variables have high F-values and are highly significant at each step of the model, but the constant is not significant (0.079) in the last step. Should I disregard all the results just because of...