Data analysis probability and significance and choosing a statistical test

Question 1

What is probability ?

Answer 1

The likelihood that a particular event or outcome will occur

Question 2

What is significance ?

Answer 2

The association between two or more variables is strong enough for us to accept the experimental hypothesis.

Question 3

How do we determine critical values ?

Answer 3

• Whether the hypothesis was one or two tailed.
• Number of ppts in the sample
• p- value level of confidence in findings

Question 4

What is the difference between one tailed and two tailed ?

Answer 4

One tailed - Hypothesis there will significantly more words recalled in the same context.

Two tailed - There will be a difference .

Question 5

What is type I error ?

Answer 5

’ False positive’
When the null hypothesis is rejected and it should not have been,
-When there is a significance level of 5% we are giving are ourselves 5% probability of incorrectly rejecting the null hypothesis.
-For example, when a tests shows a patient to have a disease when in fact they don’t

Question 6

How can we reduce the chance of a type I error ?

Answer 6

1 set a more stringent / more demanding
2 use the 0.025 level.

Question 7

What is Type II error ?

Answer 7

‘False negative’
- When the null hypothesis is accepted and it shouldn’t have been.
For example, a blood test failing to detect the disease it was designed to detect, in a patients who really has the disease.

Question 8

Before choosing a statistical test, the researcher must establish what ?

Answer 8

1 Looking for a difference or relationship.
2 Research design independent or repeated measures.
3 Type of data

Question 9

What are the 3Ds ?

Answer 9

What is the difference
What type of data
What type of design