# Tagged Questions

IBM SPSS Statistics (formerly SPSS, i.e. "Statistical Package for the Social Sciences") is a proprietary cross-platform general-purpose statistical software package. [For SPSS Modeler, use 'spss-modeler' tag.]

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### Python as a statistics workbench

Lots of people use a main tool like Excel or another spreadsheet, SPSS, Stata, or R for their statistics needs. They might turn to some specific package for very special needs, but a lot of things can ...
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### Why is “statistically significant” not enough?

I have completed my data analysis and got "statistically significant results" which is consistent with my hypothesis. However, a student in statistics told me this is a premature conclusion. Why? Is ...
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### Is PCA followed by a rotation (such as varimax) still PCA?

I have tried to reproduce some research (using PCA) from SPSS in R. In my experience, principal() function from package psych ...
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### When is R squared negative?

My understanding is that R squared cannot be negative as it is the square of R. However I ran a simple linear regression in SPSS with a single independent variable and a dependent variable. My SPSS ...
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### Fisher's Exact Test in contingency tables larger than 2x2

I was taught to only apply Fisher's Exact Test in contingency tables that were 2x2. Questions: Did Fisher himself ever envision this test to be used in tables larger than 2x2 (I am aware of the ...
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### Choice between Type-I, Type-II, or Type-III ANOVA [duplicate]

We have a dataset with three variables (dV: self-reported measure on scale 1-5, assumed to be metric; iV1: factor with 4 levels; iV2: factor with 8 levels). We are interested whether the dV differs in ...
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### Difference between generalized linear models & generalized linear mixed models in SPSS

I am wondering what the differences are in SPSS between analyze-> generalized linear models-> generalized linear models & ...
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### Visualizing Likert responses using R or SPSS

I have 82 respondents in 2 groups (43 in Group A and 39 in Group B) that completed a survey of 65 Likert questions each ranging from 1 – 5 (strongly agree - strongly disagree). I therefore have a ...
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### Best way to get started with and learn R

I have tried several times to "go it on my own" - but with limited success. I am a casual SPSS user and some SAS experience. Would appreciate a pointer or two from someone who has similar background ...
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### Best factor extraction methods in factor analysis

SPSS offers several methods of factor extraction: Principal components (which isn't factor analysis at all) Unweighted least squares Generalized least squares Maximum Likelihood Principal Axis Alpha ...
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### CHAID vs CRT (or CART)

I am running a decision tree classification using SPSS on a data set with around 20 predictors (categorical with few categories). CHAID (Chi-squared Automatic Interaction Detection) and CRT/CART (...
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### Stepwise logistic regression and sampling

I am fitting a stepwise logistic regression on a set of data in SPSS. In the procedure, I am fitting my model to a random subset that is approx. 60% of the total sample, which is about 330 cases. ...
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### Doing principal component analysis or factor analysis on binary data (using SPSS)

I have a dataset with a large number of Yes/No responses. Can I use principal components (PCA) or any other data reduction analyses (such as factor analysis) for this type of data? Please advise how I ...
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### Interpreting discrepancies between R and SPSS with exploratory factor analysis

I am a graduate student in computer science. I have been doing some exploratory factor analysis for a research project. My colleagues (who are leading the project) use SPSS, while I prefer to use R. ...
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### Difference between binomial, negative binomial and Poisson regression

I am looking for some information about the difference between binomial, negative binomial and Poisson regression and for which situations are these regression best fitted. Are there any tests I can ...
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### Better Classification of default in logistic regression

Full Disclosure: This is homework. I've included a link to the dataset ( http://www.bertelsen.ca/R/logistic-regression.sav ) My goal is to maximize the prediction of loan defaulters in this data set. ...
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### Displaying Ordinal Data - Means, Medians, and Mean Ranks

I have some ordinal data that is not normally distributed, so I decided to do non-parametric testing using the Mann-Whitney U Test. I am looking at differences between groups for seven scores - these ...
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### Multiple imputation for missing values

I would like to use imputation for replacing missing values in my data set under certain constraints. For example, I'd like the imputed variable x1 to be greater ...
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### Internet statistics resources suitable for psychology students doing research

I am working on a new webpage for my part-time job as a methodological/statistical consultant for (psychology) students at my university. On this website I would like to place several links to online ...
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### Understanding repeated measure ANOVA assumptions for correct interpretation of SPSS output

I am investigating whether different reward conditions may affect task performance. I have data from a small study with two groups, each with n=20. I collected data on a task that involved performance ...
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### Differences in kurtosis definition and their interpretation

I have recently realised that there are differences in the kurtosis values provided by SPSS and Stata. See http://www.ats.ucla.edu/stat/mult_pkg/faq/general/kurtosis.htm My understanding is that the ...
48k views

### How to deal with non-binary categorical variables in logistic regression (SPSS)

I have to do binary logistic regression with a lot of independent variables. Most of them are binary, but a few of the categorical variables have more than two levels. What is the best way to deal ...
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### How to test for normality in a 2x2 ANOVA?

Study Design: I showed participants some information about sea-level rise, focusing the information in different ways, both in terms of the time-scale and the magnitude of potential rise. Thus I had a ...
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### Multinomial logistic regression assumptions

What are the proper assumptions of Multinomial Logistic Regression? And what are the best tests to satisfy these assumptions using SPSS 18?
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### Can I use multiple regression when I have mixed categorical and continuous predictors?

It looks like you can use coding for one categorical variable, but I have two categorical and one continuous predictor variable. Can i use multiple regression for this in SPSS and if so how? thanks!
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### Unexpected singularities in the Hessian matrix error in multinomial logistic regression

I have been doing multinomial logistic regression analysis using SPSS 19. I have encountered the following problem when I run the analysis procedure: "Unexpected singularities in the Hessian ...
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### Balanced repeated measures design

Okay this is my problem: I have 12 participants. Each participant spent 3 nights in my lab doing a reaction time task at four timepoints during the night(12, 1, 2 and 3 oclock), with one week ...
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### Testing whether two regression coefficients are significantly different

I'm hoping somebody can help me out with this question. For a study I did a path analysis, which looks like this: IV --> Mediatior --> DV IV --> ...
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### When is it acceptable to use only two items (variables) per factor in factor analysis?

I have a set of 20 variables that I have put through factor analysis in SPSS. For purposes of the research, I need to develop 6 factors. SPSS has shown that 8 variables (out of 20) have been loading ...
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### Bonferroni correction with Pearson's correlation and linear regression

I am running stats on 5 IVs (5 personality traits, extroversion, agreeableness, conscientiousness, neuroticism, openness) against 3 DVs Attitude to PCT, Attitude to CBT, Attitude to PCT vs CBT. I also ...
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### Hypothesis testing that one time-series of a measure of entropy doesn't belong to a population

Disclaimer: I'm a software engineer, not a statistician, so please forgive any blunt error :-) I have a set of time-series "curves", each measuring the entropy of a given artifact. Now, I'm standing ...
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### Multiple imputation questions for multiple regression in SPSS

I am currently running a multiple regression model using imputed data and have a few questions. Background: Using SPSS 18. My data appears to be MAR. Listwise deletion of cases leaves me with only ...
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### Logistic Regression: Classification Tables a la SPSS in R

In SPSS output there is a pretty little classification table available when you perform a logistic regression, is the same possible with R? If so, how?
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### How to correctly treat multiple data points per each subject

I am currently arguing with someoe on how to correctly treat data with multiple measurements for each subject. In this case data was gathered for each subject within a short time for different ...
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### Interaction in generalized linear model

I have 2 continuous variables as my predictors and the interaction between them, so 3 effects all together (when I center my predictors only the interaction is significant). I am using a binary logit ...
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### Strange outcomes in binary logistic regression in SPSS

I did a binary logistic regression with SPSS 23 and I found some strange outcomes. This is for NOACprev until No_Prev_treatment, the last 6 variables. First of all they have very high outcomes for B, ...
16k views

### What to do when assumptions are not met in a chi squared test?

I am doing an analysis on a “a priori segmentation”. In order to examine significant differences between the two segments crosstabs and the chi-square test were used. Type of variables: categorical ...
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### How to perform pooled cross-sectional time series analysis?

For 86 companies and for 103 days, I have collected (i) tweets (variable hbVol) about each company and (ii) pageviews for the corporate wikipedia page (...
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### Very different results of principal component analysis in SPSS and Stata after rotation

For my PhD thesis I have to do a Principal Component Analysis (PCA). I didn't find it too difficult in Stata and was happy interpreting the results (I know there is a difference between factor and ...
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### Getting an average measurement based on two raters for cases where data is missing for one rater

Context: I'm investigating behaviour in a clinical study involving children. I had both parents and teachers completing questionnaires to inform an understanding of the same underlying constructs, ...
12k views

### Post hoc test in a 2x3 mixed design ANOVA using SPSS?

I have two groups of 10 participants who were assessed three times during an experiment. To test for differences between groups and across the three assessments, I ran a 2x3 mixed design ANOVA with <...
### Wald vs. LR $\chi^2$ tests in SPSS generalized linear models
I'm using the generalized linear models function in SPSS with a normal distribution and identity link function. If I choose the likelihood ratio $\chi^2$ statistic, I get the same results as the ...