AP Stats - Interpretations

standard deviation

standard deviation

the context typically varies SD from the mean of _______.

percentile

percentile% of context are less than or equal to value

z-score

specific value with context is z-score standard deviations above/below the mean

correlations (r)

the linear association between x-context and y-context is weak/moderate/strong and positive/negative.

residual

the actual y-context was residual above/below the predicted value when x-context.

y-intercept

the predicted y-context when x=0 context is y-intercept

slope

the predicted y-context increases/decreases by slope for each additional x-context.

standard deviation of residuals

the actual y-context is typically about s away from the value predicted by the lsrl

coefficient of determination (r2)

about r2% of the variation in y-context can be explained by the linear relationship with x-context

probability P(A)

after many many context, the proportion of times that context A will occur is about P(A)

conditional probability P(A|B)

Given context B, there is a P(A|B) probability of context A

expected value (mean)

if the random process of context is repeated for a very large number of times, the average number of x-context we can expect is expected value

binomial mean

after many, many trials the average # of success context out of n is mean.

binomial standard deviation

the number of success context out of n typically varies by stand deviation from the mean of _____.

standard deviation of sample proportions

the sample proportion of success context typically varies by std dev from the true proportion of _____.

standard deviation of sample means

the sample mean amount of x-context typically varies by std dev from the true mean of _____.

confidence interval (A, B)

we are % confident that the interval from A to B captures the true parameter context

confidence level

if we take many, many samples of the same size and calculate a confidence interval for each, about confidence level % of them will capture the true parameter in context.

p-value

assume Ho in context, there is a p-value probability of getting the observed result or more extreme, purley by chance

conclusion for a significance test

because p-value </> a, we reject/fail to reject Ho. We do/do not have convincing evidence for Ha in context.

type 1 error

the Ho context is true, but we find convincing evidence for Ha context.

type 2 error

the Ha context is true, but we don't find convincing evidence for Ha context.

power

If Ha context is true at a specific value, there is a power probability the significance test will correctly reject Ho.

Standard error of the slope

The slope of the sample LSRL for x-context and y-context typically varies from the slope of the population LSRL by about SE.