Probability & Significance Quiz

What does the null hypothesis state?

• There is a difference between conditions.

• There is no difference between conditions.

• The alternative hypothesis is true.

• The significance level is 10%.

What is the usual significance level in psychology?

• 1%

• 10%

• 5%

• 0.5%

What must the calculated value be compared with to determine significance?

• A random value

• A critical value

• A mean value

• A median value

What type of test might be required when using tables of critical values?

• One-tailed or two-tailed test

• Three-tailed test

• Four-tailed test

• No-tailed test

What is a Type I error?

• Incorrect acceptance of a false null hypothesis

• Incorrect rejection of a true null hypothesis

• Correct acceptance of a true null hypothesis

• Correct rejection of a false null hypothesis

What is a Type II error?

• Incorrect acceptance of a false null hypothesis

• Incorrect rejection of a true null hypothesis

• Correct acceptance of a true null hypothesis

• Correct rejection of a false null hypothesis

When is a more stringent significance level, such as 1%, recommended?

• When the study is a one-off or has a human cost

• When the study is repeated multiple times

• When the study is about animals

• When the study is about plants

What is more likely if the significance level is too lenient?

• Type I error

• Type II error

• No error

• Both Type I and Type II errors

What is more likely if the significance level is too stringent?

• Type I error

• Type II error

• No error

• Both Type I and Type II errors

What is the nature of a Type I error?

• Optimistic error

• Pessimistic error

• Neutral error

• Random error