Chapter 9

Question 1

significance test

Answer 1

formal procedure for using observed data to decide between two completing claims (hypotheses)
claims usually statements about parameters

Question 2

null hypothesis

Answer 2

claim we want evidence against (Ho)

Question 3

alternative hypothesis

Answer 3

Claim we want evidence for (Ha)

Question 4

one sided alternative hypothesis

Answer 4

one-sided if it states the parameter is greater than or less than the null value
one or the other

Question 5

two-sided alternative hypothesis

Answer 5

two-sided if it states the parameter is different from the null value
could be greater than or less than, it just can’t be the null value

Question 6

P-value

Answer 6

the probability of getting evidence as strong as or stronger for Ha when Ho is true

Question 7

significance level

Answer 7

the value we use as a boundary for deciding whether and observed result is unlikely to happen by chance alone when the null hypothesis is true

Question 8

Type I error

Answer 8

happens if we reject Ho when Ho is true
the data gave convincing evidence Ha is true when Ha is false

Question 9

Type II error

Answer 9

happens if we fail to reject Ho when Ha is true
the data did not give convincing evidence Ha is true when it is

Question 10

standard test statistic

Answer 10

measures how far a sample statistic is from what we would expect if Ho is true in standard deviation units
(statistic - parameter)/(standard deviation (error) of statistic)

Question 11

power

Answer 11

the probability that the test will find convincing evidence for Ha when a specific alternative value of the parameter is true