27 terms

AP Statistics Vocab Set 2

math vocab helping to prepare for the AP Stats test
Middle value. Usually used when data is skewed
1st Quartile
25% of data lies below
3rd Quartile
75% of data lies below
Interquartile Range (IQR)
5 Number Summary
Same as a box and whisker plot (min, max, Q1, Q3, Median)
A measure of center used when data are symmetric
Standard Deviation
Measure of Spread - tells the average distance each value is away from the mean
Time Plot
Displays data that change over time
A population measure
A sample measure that is calculated from a set of data
Tells how many standard deviations a value is away from the means. They do not have units, so we can compare two different values.
65-95-99.7 Rule
Says 68% fall within 1 standard deviation, 95% of data fall within 2 standard deviations, 99.7% of data fall within 3 standard deviations
Response Variable
Variables that you hope to predict or explain (Y)
Explanatory Variable
Variables that you can use to account for, explain or predict the Y variable (X)
Correlation Coefficient
A number that measures direction and strength of a linear association
Lurking Variable
A variable other than X and Y that affects both variables accounting for the correlation between the two
Differences between data values and corresponding predicted values
b₁ gives a value in Y units per X
b₀ is the value of Y when X is zero
Standard deviation of residuals
Overall measure of how successful the regression is in linearly relating Y to X
When we use regression to predict the future
Data points that pull the line lose to them so they can have a great effect on slope and intercept
Influential point
A point that when omitted will give very different results
Ladder of Powers
Places an order to re-expression we must do
Shows relationship between two quantitative variables