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gsum calculates summary statistics for an ordinal variable were each category represents a range of a conceptually continuous variable. gsum provides the weighted N, the mean, the standard deviation, and quantiles 0.25, 0.50 (the median), and 0.75 (you can specify any set of quantiles you want). Each quantile is available as both the midpoint of the category in which the quantile falls, or as a linear interpolation of that quantile based on methods presented by Blalock (1979). gsum can also produce a value table (which can also be saved) listing each category, the range, the midpoint of that range, the number of cases, the weight of each case, and the cumulative distribution function (CDF). For an extra tool, gsum can also create a new variable that contains the midpoints. gsum accepts any type of [weight] and is byable. For example, you may have a variable age_cat where 1 represents 18-24 years of age, 2 represents 25-44 years of age, and 3 represents 45-100 years of age. You can use gsum to calculate summary statistics such as the mean, median, and standard deviation. -Eric * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/statalist/faq * http://www.ats.ucla.edu/stat/stata/