Flashcards in Inferential Statistics Deck (22)

Loading flashcards...

1

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

### Inferential Statistics

2

## Population

### The complete collection to be studied

3

## Sample

### part of the population of interested selected for the study

4

## Sampling errors

### differences between the sample values and population values

5

## Sample selection is required to be __

###
random

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

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

6

## Sampling distribution of a statistic

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

7

## Sampling distribution of means

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

8

## Sampling distribution of means formula

###
𝑠/√𝑛

where n = sample size

9

## Common use of Inferential Statistics

###
estimate population parameters

compare between groups

10

## SHT procedure

###
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

11

## p value

###
major resulting value of running a SHT

quantifies how consistent your sample values are with null hypothesis

ranges from 0-1

12

## large p value

###
closer to 1:

sample values are consistent with null hypothesis

13

## small p-value

###
closer to 0:

sample values are not consistent with null hypothesis

14

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

###
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.

15

## if p > .05 you can decide that

### observed difference is not significant

16

## if p < .05 you can decide that

### observed difference is significant

17

## Potential errors for SHT

###
any one decision can be correct or incorrect

it can be classified into four possible decision outcomes

18

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

### Type I error

19

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

### correct

20

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

### Type II error

21

## If the CI contains a null value:

### the effect is not significant

22