# Chapter 2: Exploring Data with Graphs and Numerical Summaries

## Document Summary

Chapter 2: exploring data with graphs and numerical summaries. Outline: type data, qualitative or categorical data: Continuous data: organizing data and describing patterns: Box - plot: numerical measures of central tendency: Standard deviation: standardized values (z-values), outliers. Variable: any relevant characteristic observed in the subjects in a study. Class intervals: the interval for a data set made for plotting data. Class boundaries: the boundary of a interval made for plotting data. Class frequency: the frequency of a set of data. Cell frequency: the frequency of a cell of data. Relative frequency: the frequency as a percentage of the whole set of data. Variablescategorical or qualitativenominalordinalmeasurement or quantativediscretecontinuousrelative frequency = frequency sample size. Center: the measure of the center of the data. Spread: the measure of the variation in data. Outlier: an observation that falls well above or well below the overall bulk of the data. Categorical (qualitative) variable: a statistical trait that is only classi ed in categories.