Statistics

[Jessica]

Statistics is the science of data.

Individual: An object described by data
Variable: Characteristic of the individual

Categorical Variable: Places individual into one of several groups or categories.

• Pie charts show the distribution of a categorical variable as a "pie" whose slices are sized by the counts or percents for the categories. All items must be of the same family.
• Bar graphs represent each category as a bar whose heights show the category counts or percents. If there are a lot of items, it is best to use a bar graph.

Quantitative Variable: Takes numerical values for which arithmetic operations make sense.

• Histograms show the distribution of a quantitative variable by using bars whose height represents the number of individuals who take on a value within a particular class.
• Stemplots separate each observation into a stem and a leaf that are then plotted to display the distribution while maintaining the original values of the variable.

[Jessica]