Bruce Weaver on the SPSS Nabble site pointed out that the Centre for Multilevel Modelling has added some syntax files for multilevel modelling for SPSS. I went through the tutorials (in R and Stata) a few years ago and would highly recommend them. Continue reading Smoothed regression plots for multi-level data

When interpreting regression model coefficients in which the predictions are non-linear in the original variables, such as when you have polynomial terms or interaction effects, it is much simpler to make plots of the predicted values and interpret those than it is to interpret the coefficients directly.
This came up in some discussion of interpreting polynomial... Continue reading Plotting interactions and non-linear predictions

Although as I mentioned in this post on circular helio bar charts, polar coordinates are unlikely to be as effective as rectilinear coordinates for most types of comparisons, I really wanted to use a circular histogram in a recent paper of mine. The motivation is I have circular data in form of azimuths... Continue reading Using circular dot plots instead of circular histograms

I debated on pulling an Andrew Gelman and adding a ps to my prior Junk Charts Challenge post, but it ended up being too verbose, so I just made an entirely new follow-up. To start, the discussion has currently evolved from this series of posts;
The original post on remaking a great line chart by... Continue reading Why I feel SPSS (or any statistical package) is better than Excel for this particular job

I've written a macro to conduct aoristic analysis with SPSS. Here I will briefly describe what it is, provide alternative references and demonstrate some of its utility on example data from Arlington PD.
In short, crime event data are frequently recorded as occurring within some indefinate time frame. For example, you may park your car and... Continue reading Aoristic analysis with SPSS

When you have a large N scatterplot matrix, you frequently have dramatic over-plotting that prevents effectively presenting the relationship. Here I will give a few quick examples of simple ways to alter the typical default scatterplot to ease the presentation. I give examples in SPSS, although I suspect any statistical packages contains these options to... Continue reading Visualization techniques for large N scatterplots in SPSS

It seems like I have come across alot of posts recently about visualizing univariate distributions. Besides my own recent blog post about comparing distributions of unequal size in SPSS, here are a few other blog posts I have recently come across;
Nathan Yau has a recent post on his flowing data blog, How to... Continue reading Bean plots in SPSS

The other day I was reading Nathan Yau's Visualize This, and in his chapter on visualizing multi-variate relationships, he brought up star plots (also referred to as radar charts by Wikipedia). Below is an example picture taken from a Michael Friendly conference paper in 1991.
One of the things that came to mind when... Continue reading Reference lines for star plots aid interpretation