# 03 Hypotheses Flashcards

errors in statistical hypothesis tests

Type 1: Rejecting the null hypothesis when it is true

Type 2: Not rejecting the null hypothesis when it is false

significance level

The significance level is the probability of rejecting the null hypothesis when it is in fact true

significance probability

The probability of drawing a statistic at least as adverse to the null hypothesis as the one you computed in your sample, assuming that the null hypothesis is true.

power

the probability of correctly rejecting the null hypothesis when the alternative is true

the probability of correctly rejecting the null hypothesis when the alternative is true

power

The probability of drawing a statistic at least as adverse to the null hypothesis as the one you computed in your sample, assuming that the null hypothesis is true.

significance probability

the probability of rejecting the null hypothesis when it is in fact true

significance level

Rejecting the null hypothesis when it is true

Type 1 error

Not rejecting the null hypothesis when it is false

Type 2 error

standard error of the sample average

SE(\bar{Y}) = ^σ_ ̄Y = s_Y / root(n)

sample variance

s^2_Y = 1 / (n - 1) * Sum[ (Yi - ̄Y)^2 ]

an estimator for the population variance

sample variance

s^2_Y = 1 / (n - 1) * Sum[ (Yi - ̄Y)^2 ]

sample variance

SE( ̄Y) = ^σ_ ̄Y = s_Y / root(n)

standard error of the sample average

The t-test is used when the ____ is unknown

The t-test is used when the population standard deviation is unknown