
Individuals
objects described by the data, e.g. people, plants, animal

Variable
characteristic of individual, e.g. age, blood pressure, height, weight, eye color

Two types of variables:
Categorical & Quantitative

Categorical
falls into a category – cannot be added, e.g. color, gender

Quantitative
 can be counted or measured – can be added, subtracted, e.g.
 income

Charting categorical data
Bar graph & Pie chart

Bar graph
each category represented by a bar, record frequency for each category

pie chart
slices must represent the parts of one whole

Charting quantitative data (shape, center, spread)
histogram, stem plot, time plot

Histogram
 Choose the classes
 Count the individuals in each class
 Draw the histogram

Stem plot
 may be able to split stems
 Numerical histogram
 Note symmetry/ skewness; outliers

Time plot
time on the xaxis (horizontal)

