Probability and significance

Question 1

What is a level of significance

Answer 1

This is a point where researcher’s can claim to have discovered a significant difference or correlation

Question 2

The usual level of significance

Answer 2

5% / 0.05. When the researcher has found a significance, there is a 5% probability results occurred by chance.

Question 3

Type II error

Answer 3

• too pessimistic
• false negative
• Researcher has accepted the null and rejected the alternative (should have been other way around)
• Think nothing is happening when it is#
• More common with stringent levels significance

Question 4

Type I error

Answer 4

• too optimistic
• false positive
• rejected the null and accepted the alternative, should be the other way around
• Think something is happening when it isn’t
• More common with lenient levels of significance

Question 5

Strict level of significance

Answer 5

• 0.01 (1%)
• Used when the study is non repeatable like studies on side effects of drug therapies

Question 6

More lenient level of significance

Answer 6

• 0.10 (10%)
• Used when researcher’s results won’t be seen as significant but it gives power to the researcher.