AP Statistics Unit 1: Exploring Data

The values a variable takes on and how often it takes on those values

A recorded characteristic of an individual

When we place an individual into categories or groups

How many times a variable is recorded (counts)

How many times a variable is recorded (%)

Relative frequency compared to a whole

Rectangular bars that don't touch

Useful when comparing two groups

Describes how the data looks on a graph

The values on either side of the mean or median are roughly equal. (Mean = Median)

The left tail of the graph is longer than the right (Mean<Median)

The right tail of the graph is longer than the left (Mean>Median)

Shows up as a straight horizontal line on a graph where are outcomes are equally likely

Has one peak

Has two peaks

Has multiple peaks

A variable where the data represents numerical amounts

: dot plot, box plot, stem plot, histogram

Points that are unusually small or large compared to the whole group

The average

Halfway point

The difference from the lowest score in the distribution to the highest score.

Represents the middle 50% of the data

Average distance from the mean

Maximum - minimum

Higher, lower, similar (comparing words)

Min, Q1, Median, Q3, Max

A common measure of spread (Always positive, average distance from the mean)

The percent of observations at or below a value

The bottom 25% of the data

The value where 75% of data points are found equal to or below when arranged in an increasing order

(n+1)/2

Q3-Q1