Exam One - Confidence Intervals

Question 1

Inferential stats are used to…

Answer 1

1 - estimate pop characteristics using sample data
2 - test for effects (hypothesis testing and relationships)

Question 2

population

Answer 2

all possible cases of a particular measur

Question 3

sample

Answer 3

subset of cases drawn from the population

Question 4

the more cases you sample, the more _______ you can be your sample represents the pop well

Answer 4

confident

Question 5

sampling error

Answer 5

each sample results in a different estimate of the pop mean

Question 6

____samples will result in “better” estimates of the pop mean

Answer 6

larger

Question 7

Standard error of the mean (SE)

Answer 7

estimate how far the sample mean is likely to be from the pop mean

Question 8

SE =

Answer 8

(sample SD)/(square root of sample size)

Question 9

What is the effect of a larger sample on our pop estimate?

Answer 9

decreased SE

Question 10

what is the effect of increased sample variability on our pop estimate

Answer 10

increased SE

Question 11

confidence interval

Answer 11

range of values the true pop mean is expected to lie within

Question 12

CI =

Answer 12

sample mean +/- t(sample sd/square root sample size)

Question 13

the ______- is based on sample size and desired level of confidence

Answer 13

t statistic

Question 14

Will a large sample size make CI wider or narrow?

Answer 14

narrow

Question 15

will large sample variability make CI wider or narrow?

Answer 15

wider

Question 16

will a desire for greater confidence in our estimate be wider or narrow

Answer 16

wider

Question 17

CI tells you

Answer 17

1 - range of values the actual pop mean is likely within
2 - cutoffs for mean sample values that are expected and those that arent