AP Stats Chpt 7 Flashcards

14846204666	Model	an equation or formula that simplifies and represents reality	0
14846206590	Linear Model	An equation of a line. To interpret a linear model, we need to know the variables and their units.	1
14846209923	predicted value	found by substituting the x-value in the regression equation; they're the values on the fitted line	2
14846213832	residual	the differences between data values and the corresponding values predicted by the regression model	3
14846222160	Least squares	This criterion specifies the unique line that minimizes the variance of the residuals, or equivalently, the sum of the squared residuals.	4
14846233657	regression to the mean	Since the correlation is always less than 1 in magnitude, each predicted y-hat tends to be fewer standard deviations from its mean than its corresponding x was from its mean.	5
14846247967	regression line (line of best fit)	the particular linear equation that satisfies the least squares criterion	6
14846251484	Slope	This gives a value in y-units per x-unit.	7
14846261247	Intercept	This is the starting value in y units. It is the y-hat value when x is 0.	8
14846273255	R^2	Coefficient of determination. Gives the fraction of the variability of y accounted for by the LSRL on x.	9
14846286913	Does the Plot Thicken? Condition	the scatterplot or residuals plot should show consistent (vertical) spread in y-values	10
14846294533	Standard deviation of the residuals	Gives the approximate size of a "typical" prediction error.	11