AP Statistics Interpretations Percentile: The % of values that are less than or equal to a given value. Standard Deviation: The fill in context typically vary by (standard deviation value) from the mean fill in context of (mean value). Mean: If many, many fill in context are randomly selected, their average fill in context will be about (mean value). Scatter plots: DUFS Direction Usual features Form (linear/non-linear) Strength P-value: Assuming that the parameter (proportion or mean) of fill in context, there is a fill in probability of getting a sample (proportion or mean) of fill in sample proportion/mean value or (bigger or smaller) by chance alone in random samples of size n. P-value for a difference in means: Assuming the true difference in mean difference (A – B) fill in context is zero, there is a P-value probability that we would observe a mean difference of sample mean difference or greater/lesser by chance alone. Coefficient of determination, r 2 : “% of the variation in (response variable name) is accounted for by the regression line when x = (explanatory variable name).” r: direction (+/-); form (always linear); strength – use an “ly” word if in-betweens. y-intercept: when x = 0, the predicted (y-context) is (y-intercept). Slope: with each additional (x-context) the predicted (x-context) increases/decreases by (slope). Statistically significant: The difference found fill in context of (difference value) was large/small enough that it was unlikely to occur by chance alone. Conclusion of significance testing: Because the p-value of ___ is greater/less than α = ___; we reject/fail to reject the H0. . We do/do not have convincing evident for Ha. in context. Power: : If the true (proportion) fill in context, is fill in parameter that satisfies the Ha (this number will be given to you as p = that is different from H0 ), there is a fill in Power probability of finding convincing evidence to reject Ho in context. Confidence level: If we constructed many, many confidence intervals from random samples of this size, approximately C% of the intervals would capture the true population parameter. In context. Confidence interval: We are C% confident that the interval from ____ to ____ captures the true value of the population parameter in context.