SPSS (Statistical Package for the Social Sciences) is a proprietary cross-platform general-purpose statistical software package.

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200
votes
21answers
65k views

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 ...
33
votes
7answers
3k views

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 ...
20
votes
4answers
20k views

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 ...
18
votes
3answers
22k views

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 ...
16
votes
4answers
7k views

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 ...
15
votes
11answers
2k views

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 ...
14
votes
4answers
5k views

is psych::principal function still PCA when using rotation?

I have tried to reproduce some research (using PCA) from SPSS in R. In my experience, principal() function from package psych ...
12
votes
3answers
9k views

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 & ...
12
votes
3answers
2k views

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. ...
11
votes
5answers
2k views

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. ...
10
votes
3answers
4k views

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 ...
10
votes
1answer
3k views

Best factor extraction methods, with reference to SPSS

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 ...
9
votes
3answers
4k views

Choice between Type-I, Type-II, or Type-III ANOVA

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 ...
8
votes
4answers
260 views

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 ...
8
votes
3answers
8k views

Sidak or Bonferroni?

I am using a generalized linear model in SPSS to look at the differences in average number of caterpillars (non-normal, using Tweedie distribution) on 16 different species of plants. I want to run ...
8
votes
2answers
20k 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 ...
8
votes
1answer
2k views

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 ...
7
votes
5answers
3k views

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. ...
7
votes
2answers
363 views

SPSS and Stata output different

I'm Stata-proficient but learning SPSS for my new position. I am using a simple dataset to do very basic regressions and comparing to see if the results are the same. They're not. I'm close, but the ...
7
votes
4answers
3k views

Is 0 a valid value in a Likert scale?

I have carried out my pilot study on language learning motivation using a 6 point Likert scale but from 0 (strongly disagree) to 5 (very much agree). I noticed a colleague in his survey used 1 to 6. ...
7
votes
2answers
1k views

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 ...
7
votes
2answers
8k views

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 ...
7
votes
3answers
4k views

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: ...
7
votes
1answer
8k views

How to perform principal components 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 ...
7
votes
2answers
5k views

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 ...
7
votes
3answers
1k views

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?
7
votes
2answers
6k views

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 ...
7
votes
0answers
915 views

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 ...
7
votes
2answers
143 views

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 ...
6
votes
3answers
3k views

Calculating eta squared from F and df

I'm trying to compute ANOVA effect sizes from papers that provide an F value without other information. If I understand correctly, the effect size for a single-factor ANOVA is $$ \eta {2} = ...
6
votes
4answers
2k views

Comparing logistic regression coefficients across models?

I've developed a logit model to be applied to six different sets of cross-sectional data. What I'm trying to uncover is whether there are changes in the substantive effect of a given independent ...
6
votes
3answers
1k views

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 ...
6
votes
4answers
6k views

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 (...
6
votes
3answers
11k views

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!
6
votes
1answer
116 views

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, ...
6
votes
2answers
475 views

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 ...
6
votes
1answer
475 views

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 ...
6
votes
1answer
1k views

How to do a repeated measures multinomial logistic regression using SPSS?

Question: Can you do a repeated measures multinomial logistic regression using SPSS? Context: I need to do a regression on data at two points of time and I think this maybe the only way to go(?). ...
6
votes
1answer
498 views

Derivation of distance in two-step clustering

I am working with the two step cluster process in SPSS Modeler (Clementine) and trying to get a sense for the distance function used. It is a log-likelihood function (as stated in docs) but I am ...
5
votes
3answers
1k views

My distribution is normal; Kolmogorov-Smirnov test doesn't agree

I have a problem with the normality of some data I have: I've done a Kolmogorov test which says it isn't normal with p=.0000, I don't understand: the skewness of my distribution =-.497, and the ...
5
votes
2answers
287 views

Can statistical prediction be asymmetric?

Thus can we have random variables $X_1 , ... , X_n$ , each with zero mean and unit variance, such that for a sizeable representative sample: (1) in the least-squares regression equation for $X_1$ ...
5
votes
5answers
372 views
+100

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 ...
5
votes
2answers
3k views

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?
5
votes
4answers
5k views

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 ...
5
votes
1answer
631 views

Justification for low/high or tertiary splits in ANOVA

I have two groups of participants and they all took the same measurements. When I perform a median split on one of the measurements to test my hypothesis about an interaction, the dependent ...
5
votes
3answers
4k views

How to calculate an overall job satisfaction score and test group differences?

I am doing a project on finding out whether there is a difference in job satisfaction between employees of non-profit organisations and for-profit organisations. I also need to find whether job ...
5
votes
2answers
236 views

Correlation between vegetation and erosion

I am wanting to find the correlation between two variables: a categorical vegetation variable (with categories 1-4) and a continuous variable of erosion (with values anywhere between 0.2 and 9). I ...
5
votes
2answers
7k 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 ...
5
votes
2answers
901 views

Cox regression when reference group had zero events

I would appreciate some advise on an a problem I ran into. I use SPSS for statistical analysis of a study. The study look into how a blood test predicts mortality with patients followup of 1 year. ...
5
votes
2answers
552 views

Longitudinal relationship between chocolate consumption and happiness: repeated measures ANOVA?

I am using SPSS and having some trouble with a research question which is analogous to the hypothetical question: Is there a longitudinal Relationship between Happiness and Chocolate Consumption? ...