chp 4

Question 1

in most cases, the null hypothesis is something researchers hope to prove ____

Answer 1

false

Question 2

results found as extreme as they are is measured by

Answer 2

p value

Question 3

expecting that true groups in an experiment are identical is known as

Answer 3

null hypothesis

Question 4

the p value proves the null hypothesis that results are due to ____ alone

Answer 4

chance

Question 5

why do we want less than 0.05 value?

Answer 5

arbitrary; bc we want to REJECT null hypothesis

- say there IS a difference and not by chance

Question 6

how is statistically significance measured

Answer 6

p value - shows there is a difference

Question 7

define null hypothesis

Answer 7

no difference among groups and that observed differences are due to random variation (chance)

Question 8

the smaller the p value the ___ the evidence is to dispute the null hypothesis

Answer 8

stronger

Question 9

numeric representation of the degree to which random variation alone could account for the differences observed between groups

Answer 9

p value

Question 10

when the null hypothesis is rejected, the result is said to be _____

Answer 10

statistically significant

Question 11

when the p value is greater than 0.05, the null hypothesis can be ____

Answer 11

accepted

– saying it did happen by chance

Question 12

the incorrect rejection of the true null hypothesis

Answer 12

type 1

• false positive
• saying there is a difference but actually not one

Question 13

incorrectly retaining a false null hypothesis

Answer 13

type 2
false negative
-saying there is no difference when there IS one

Question 14

t/f p values convey info regarding size

Answer 14

false

Question 15

what is the CI if there is a large sample

Answer 15

narrow confidence interval

Question 16

in a small sample the SEM is ___ and the CI is ____

Answer 16

larger; wider

Question 17

a test is called ____ tailed if the null hypothesis is rejected for values of the test statistic falling into either tail of its sampling distribution

Answer 17

two tailed

Question 18

test is ___ tailed if the null hypothesis is rejected only for the values of the test statistic falling into one specified tail

Answer 18

one

Question 19

which tail test is easier to achieve significance, why?

Answer 19

one tail

• bc in two tail you have more possibility (less confident) it will fall in either side..
• -> p value is HALF the two- tailed P value

Question 20

which tail test will you find a type 2 error

Answer 20

two tail

- more difficult to achieve significance

Question 21

in a one tail test, if results went other direction than predicted this means it ___ significant

Answer 21

not statistical significant

Question 22

which tail test should you have a prediction for direction

Answer 22

one tail test

Question 23

one tail has a chance for type ___ error

Answer 23

one

Question 24

which tail test is more often used?

Answer 24

two tail test

Question 25

are two tailed test more or less conservative

Answer 25

more (have to divide them into two so 0.25 each side)

Question 26

what is the threshold denoted by

Answer 26

alpha