COMM 215 Lecture Notes - Lecture 3: Standard Deviation, Quartile, Interquartile Range
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Parameter : a measure computed from the entire population. As long as the population doesn"t change, the value of the parameter will not change. Statistic : a measure computed from a sample that has been selected from a population. The value of the statistic will depend on which sample is selected. Mean: the average for all values in the population computed by dividing the sum of all values by the population size. Mean: the average for all values in the sample computed by dividing the sum of all sample values by the sample size. Median is a center value that divides a data array into two halves (md) Data array : data that have been arranges in numerical order. Median index: i = n / 2 (nb1: round up. ) In an ordered array (lowest to highest), the median is the middle value (i. e. : the number that splits the distribution in half numerically.
