hypothesis testing

null hypothesis (Ho)

a statement of no difference between a sample means or proportions

alternative hypothesis (Ha)

a claim about population that is contradictory to (Ho)

• equal to

• the same as

• not changed from

• is

keywords used to determine a null hypothesis

• ≤ (less than or equal to)

• ≥ (greater than or equal to)

• = (equal)

symbols used in null hypothesis

• not equal

• different from

• changed from

• not the same as

keywords used to determine an alternative hypothesis (≠)

• greater than

• above

• higher than

• longer than

• bigger than

• increased

• at least

keywords used to determine an alternative hypothesis (>)

• less than

• below

• lower than

• smaller than

• shorter than

• decreased or reduced from

• at most

keywords used to determine an alternative hypothesis (<)

• > ( greater than)

• < (less than)

• ≠ (not equal)

symbols used in alternative hypothesis

type I error

• when a null hypothesis is rejected when it is actually true

• rejected = true

type II error

• when the null hypothesis is not rejected when it is actually false

• accepted = false