BSB123 Lecture Notes - Lecture 2: Supreme Headquarters Allied Powers Europe, Interquartile Range, Squared Deviations From The Mean
Document Summary
Topic 2 - numerical descriptive measures (a) central location. Measure of a point around which all scores are centred. Uses all information, mathematical properties make it most useful for inference, but adversely affected by extreme observations. Median = middle value when observations are arranged in ascending order. Closest in meaning to central location, not affected by extremes as badly as mean but does not use all information. E. g. house pricing so that outlying data does not skew results. If n is odd, median is the middle number. If n is even, median is the average of the middle two numbers. Only real measure of central location for qualitative data. The distance between a data point and the mean is the deviation. Below the mean is (-) deviation and about is (+) as it is greater. The sum of the deviations should be equal to 0. Sum of all deviations (+ & -) must be equal to .
