Inferential Statistics

Question 1

To make a decision about the population group based on the information of the sample group

Answer 1

Inferential Statistics

Question 2

Population

Answer 2

The complete collection to be studied

Question 3

Sample

Answer 3

part of the population of interested selected for the study

Question 4

Sampling errors

Answer 4

differences between the sample values and population values

Question 5

Sample selection is required to be __

Answer 5

random

random selection implies all members have an equal opportunity to be chosen

doesn’t guarantee proportional representation of all parts of the population

Question 6

Sampling distribution of a statistic

Answer 6

distribution of values taken by the statistic in all possible samples of the same size from the same population

Question 7

Sampling distribution of means

Answer 7

distribution of sample means. Called standard error of the mean.

Question 8

Sampling distribution of means formula

Answer 8

𝑠/√𝑛

where n = sample size

Question 9

Common use of Inferential Statistics

Answer 9

estimate population parameters

compare between groups

Question 10

SHT procedure

Answer 10

1. state statistical hypotheses (null and alternative)
2. Select level of significance
3. Decide which test to use
4. Make a decision to reject or retain null hypothesis based on p value

Question 11

p value

Answer 11

major resulting value of running a SHT

quantifies how consistent your sample values are with null hypothesis

ranges from 0-1

Question 12

large p value

Answer 12

closer to 1:

sample values are consistent with null hypothesis

Question 13

small p-value

Answer 13

closer to 0:

sample values are not consistent with null hypothesis

Question 14

how to make decision to reject or retain null hypothesis based on p value and 𝛼

Answer 14

compare p value to preset level of significant (𝛼).

if 𝛼= 0.05 and p value < 0.05, reject null hypothesis

if p value > 0.05 retain null hypothesis.

Question 15

if p > .05 you can decide that

Answer 15

observed difference is not significant

Question 16

if p < .05 you can decide that

Answer 16

observed difference is significant

Question 17

Potential errors for SHT

Answer 17

any one decision can be correct or incorrect

it can be classified into four possible decision outcomes

Question 18

if the null hypothesis is true and you reject the null hypothesis, this is considered

Answer 18

Type I error

Question 19

if the null hypothesis is false and you reject the null hypothesis this is

Answer 19

correct

Question 20

if the null hypothesis is false and you do not reject the null hypothesis this is

Answer 20

Type II error

Question 21

If the CI contains a null value:

Answer 21

the effect is not significant

Question 22

If the CI does not contain the null value

Answer 22

effect is significant