Type l and ll errors

Question 1

When does a type 1 error occur?

1

Answer 1

• Researcher rejects null hypothesis that is true

Question 2

When does a type 2 error occur?

1

Answer 2

• Researcher accepts null hypothesis that was not true

Question 3

What does a 10% level of significance suggest and a drawback of this?
3

Answer 3

• Too lenient
• Increases chance type 1 error
• Content to be less certain

Question 4

What does a 1% level of significance suggest and a drawback of this?
3

Answer 4

• Wish to be more certain
• Medical research
• Too stringent, ^chance of type 2 error

Question 5

What are the features of a normal distribution? 3

Answer 5

• Bell shape - Occurs when certain variables are measured (IQ) - All measures of central tendency at mid point

Question 6

What are the features of a skewed distribution?

2

Answer 6

• Measures of central tendency don’t share same value

- Positive skew = most scores bunched to left

Question 7

What is the preferred level of significance?

1

Answer 7

• 0.05 or 5% probability result occurs from chance