Grouped frequency distribution definition can be described as an indicator of how many times each variable value occurs in a set of grouped observations. The frequency distribution table is one of the easiest ways to present sociological observations.
The frequency distribution table consists of at least two columns, where the left one contains the values that a variable can take, and the right one contains the number of times that each value occurs. Sometimes additional columns that reflect the percentage distribution are included.
The elements of raw data become comprehensible when they are grouped into a frequency distribution. To group the data, it must first divide the scale by which they were measured into intervals, and then calculate how many elements fall on each interval. The interval in which values are grouped is called the group interval. The decision on how many group intervals the data should be divided is not determined by any rule, but comes from the decision of the researcher.
The frequency distribution is easier to understand when it is presented graphically and the most widely used graphic form is the frequency histogram. Histograms are compiled by drawing stripes, the bases of which are set by group intervals, and the height – by the corresponding frequencies of the groups. Another way to represent the frequency distribution in graphical form is the frequency envelope. When constructing the envelope of the frequency of the groups are marked opposite the middle of the interval of the groups, and then these points are connected by straight lines. To complete the complex distribution, one more class is added at each end of the distribution, since these classes have zero frequency, both ends of the resulting figure will be on the horizontal axis. The frequency envelope gives the same information as the frequency histogram, but consists of a series of connected segments, not stripes.