COMM301 Lecture Notes - Lecture 9: Standard Deviation, Large Deviations Theory, Dependent And Independent Variables
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Data description (chapter 8 in book) - extra notes in notebook. S om e nec es s ary s y m b ols. N, nj number of observations in the data set, the subset is always lower case. Mode - most frequently obtained score: strength - simple and easy to calculate, weakness - frequency distorts the location of the middle of the data. If n is an odd number, you count down half way and there will be a score right in the middle. Mean - balance point of the data: strength - provides middle around which spread can be calculated. The mean is in the same units as the scores: weakness - distorted by extreme scores on either end of the distribution. It is really a bar graph, a histogram. In a normal distribution, the mean, median, and mode will be same number same score right in the middle. The central limit theorum: the law of large numbers.