Frequency Distribution Definition/Meaning:
A table of the number of occurrences of each of a set of
classified observations. The occurrences might arise from the throw of dice, the
measurement of a man's height in a particular range of values, or the number of
reported cases of a disease in different groups of people classified by their
age, sex, or other category. It is usual practice to choose a fairly small
number of categories so that the relative frequencies within categories are not
too small.
If no definite upper or lower limits are known, all values above (or
below) a certain value are grouped into a single category known as the upper for
lower) tail. Frequency distributions may be summarized by computing
statistics
such as the mean (or other measures of location) and the standard deviation (or
other measures of variation), and sometimes measures of asymmetry or skewness
and of compactness (i.e. the proportion of the sample in the center and in the
tails). The term frequency distribution is applied to observed data in a sample.
In contrast, probability distributions are theoretical formulas for the
probability of observing each event. Fitting probability distributions to
observed frequency distributions is a fundamental statistical method of data
analysis.
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