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I would like to ask something about histograms. I have a dataset containing only positive values. How can I get a histogram in spss25 with first range beginning a negative number? What does it mean?

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    $\begingroup$ Are you asking how to produce such a histogram or are you asking why SPSS might have produced such a histogram? $\endgroup$ – whuber Jul 17 at 21:22
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@whuber asked a good question in a comment. There are two possible answers. So:

If you are asking how to get SPSS to do such a thing, then that is off topic and should be asked on an SPSS list (although why you want it to do that is a bit of a mystery - If you have a question about that, please rephrase your question.

If you are asking about why SPSS would do such a thing, it will be because you haven't told it not to do so. That is, you've accepted the defaults. Exact coding depends on software, but other software does this too - I've seen it in R and SAS. And it's not only histograms, it's also density plots (and, as an aside, you might consider a density plot instead of a histogram - William Cleveland has strong negative opinions about histograms, and he knows more about statistical graphics than just about anyone).

The software doesn't know that your variable can't be negative. In fact, it doesn't even treat 0 as a special number. You give it data and it sorts it into bins and picks a starting point. The starting point will be lower than your lowest value, unless you tell it otherwise.

Although this can be frustrating in some situations, it's really a sensible default.

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