STATISTICS: STATISTICAL MEASURES
STATISTICAL MEASURES
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MEASURES OF SPREAD
THe aim of producing statistics is to reduce the amount of data to a small amount of figures that represent the data as well as possible, in the case of the height data, the heights group around the range of 150-160 cm. this is knownas the "central tendecny" and there are several ways of measuring this:
MODE~~~~the most frequent class of data; the class/category which appears most often.
MEAN~~~~AKA the "average" of the data. to calculate the mean, numeric data is added and the result is divided by the # of items of data that you have. there are 2 types of means:
****POPULATION MEAN-->the mean of all the data present (µ)
****SAMPLE MEAN-->the mean of a part of the possible data (x)
MEDIAN~~~~~The median is found by arranging all the data in order of size and then selecting the middle item. if there is an even number of items (in which casee there is no middle item), the mean of the two middle items is taken and this mean is the median.
