Chapter 5 and 6

Question 1

Indirect proof

Answer 1

taking the opposite of what you want to prove and assuming it is true

Question 2

What is indirect proof used for?

Answer 2

In hypothesis testing, it is used to prove the null is false

Question 3

What type of sample does a null hypothesis distribution take?

Answer 3

Random

Question 4

What type of distribution does a random sample (and null hypothesis distribution) have?

Answer 4

It will have a normal distribution that is shaped like a bell curve

Question 5

How to you find the odds of the null hypothesis being true?

Answer 5

Finding where the results fall on the null hypothesis distribution. This is done by converting the results to a z score

Question 6

Formula for z score?

Answer 6

z=x-u/ox

Question 7

What is x?

Answer 7

experimental result

Question 8

What is u?

Answer 8

population mean

Question 9

What is Ox?

Answer 9

The SD of the sampling distribution

Question 10

What is alpha?

Answer 10

The amount of risk the experimenter is taking and is set before the experiment starts

Question 11

What does it mean if the null hypothesis is rejected?

Answer 11

there is a significant difference because of the experiment’s manipulation

Question 12

What does it mean if the null is failed to reject?

Answer 12

it means that the p value is greater than what the alpha is set at, and that there is not statistical significance

Question 13

What is a Type I error?

Answer 13

when the null hypothesis is true but still rejected

Question 14

What is a Type II error?

Answer 14

when the null hypothesis is accepted when it is actually false

Question 15

What does a two tailed test do?

Answer 15

increases generalizability of test and also allows for testing of stat significance in both directions

Question 16

What is the difference in the p value between a one and two tailed test?

Answer 16

The p value needs to be doubled in two tailed tests

Question 17

Name the steps for testing the null hypothesis?

Answer 17

1. state hypothesis
2. select sig level and stat test
3. Select sample and collect data
4. Find region of rejection
5. Calculate test stat
6. Make decision

Question 18

Can you ever accept the Ho or Ha?

Answer 18

No, you can either reject the null or fail to reject

Question 19

When do you use a z test?

Answer 19

When the parameters (mean and SD) are known

Question 20

When do you use a t test?

Answer 20

when the population parameters are unknown

Question 21

how are degrees of freedom calculated?

Answer 21

N-1

Question 22

What is degrees of freedom?

Answer 22

Our best estimate of what the population SD is

Question 23

What test do you use df with?

Answer 23

T tests

Question 24

What comes with each possible number of df’s?

Answer 24

a different sampling distribution