STAT 200 Lecture Notes - Lecture 3: Interquartile Range, Box Plot, Quartile
Document Summary
Descriptive statistics: frequency distribution, relative distribution, bar chart, pie chart, stem and leaf chart. Mean: sum of the observations divided by the number of observations. Median: arrange the data in increasing order, find the middle number (if there are two numbers in the middle then us the following equation to solve: (n+n)/2) Mode: the number that occurs the most often, if none then the answer will be no mode". The sample standard deviation indicates how far on average the observations are from the mean of the sample. A sample standard deviation can be computed using the following formula: Almost all observations in any data set lie within three standard deviations on either side of the mean. The median divides the data set into two parts. 1st quartile: median of the bottom half of the data set. 2nd quartile: median of the entire set. 3rd quartile: median of the top half of the data set.
