summary statistics

13:16 Jan 3, 2009 

When summarizing a quantity like length or weight or age, it is common to answer the first question with the arithmetic mean, the median, or, in case of a unimodal distribution, the mode. Sometimes, we choose specific values from the cumulative distribution function called quantiles.

The most common measures of variability for quantitative data are the variance; its square root, the standard deviation; the range; interquartile range; and the average absolute deviation (average deviation).

12:24 Jan 3, 2009 

In descriptive statistics, summary statistics are used to summarize a set of observations, in order to communicate as much as possible as simply as possible. Statisticians commonly try to describe the observations in a MEASURE OF LOCATION, or CENTRAL TENDENCY, such as the ARITHMETIC MEAN, MEDIAN, MODE, or interquartile mean
a measure of statistical dispersion like the STANDARD DEVIATION, VARIANCE, RANGE, or interquartile range, or absolute deviation.
a measure of the shape of the distribution like skewness or kurtosis
The complete set of explanatory variables available for analyses and the summary statistics are presented in Table 1 and online Appendix 2 (available at http:// www.cdc.gov/ncidod/EID/vol12no05/05-1321_app2 .htm).
Table 1. Demographic characteristics of included patients by surgical site infection (SSI) % (no.) Characteristic No SSI SSI (n = 38) (n = 411) Age, y, MEAN (SD) 63.58 (14.41) 64.37 (13.72) Socioeconomic score (1-100),* MEAN (SD) 35.67 (19.17) 40.37 (20.53)"
grifo nosso.