STATS 7 Lecture Notes - Lecture 1: Quartile, Categorical Variable, Interquartile Range
Document Summary
Individual and variables individuals: people or the objects that we will be describing variable: any characteristic of an individual. The major types of data quantitative: a meaningful numerical value is recorded for each individual; values can be average across individuals in the data set (ex. Most common ways: o o bar graphs: used for representing one or more variables and groups pie charts: only used for representing how one homogeneous group breaks down into category subsets bar graphs: versatile, can compare several variables. We plot number of data points that fall in each class (frequency) or the percent of data points (relative frequency) Graphing time series time plot: time is on the x-axis (horizontal) trend: an overall pattern cyclical variations: regularly recurring variations. Mean: uses all the data points (affected by outliers) Median: uses only data points in the middle robust measure: not substantially affected by skews or outliers (ex. median)
