AP Stats Unit 1: Exploring One-Variable Data (RECAP)

Descriptive Statistics

Descriptive Statistics

Involves collecting, organizing, summarizing, and drawing conclusions from data.

Inferential Statistics

Making inferences and predictions from previous data.

Categorical Variable

Takes on category names or group labels.

Quantitative Variable

Involves numbers measuring quantity.

Discrete Variable

Contains gapped numerical values.

Continuous Variable

Has infinite possible values without gaps.

Frequency Table

Shows the number of individuals in each category.

Relative Frequency Table

Displays proportions or percentages of individuals in each category.

Dotplot

Represents data using dots on an axis.

Outliers

Data points outside the normal range of a distribution.

Mean

Average value calculated by summing all data points and dividing by the number of points.

Median

Middle value of ordered data.

Range

The difference between the highest and lowest data points.

Interquartile Range (IQR)

Range of the middle 50% of data.

Normal Distribution

Symmetric distribution with mean in the center and specific percentages within standard deviations.

Z Score

Measure of standard deviations a data point is from the mean.

Percentile

Percentage of data values less than or equal to a given value.

Bar Chart

represents categorical data, comparing values between groups of data

Histogram

represent quantitative data using frequencies, where each rectangles to the right of a number of the x axis represents the presence of a value between itself and the next number, minus 1.

Stem & leaf plot

represents quantitative variables by having the “stem” (singular number typically to the left of the line) represent a larger value like the tens value, while the other side is the “leaf” representing a smaller number such as the ones place value.

Uniform Distribution

Evenly distributed data throughout all values