Question

A noted psychic was tested for Extrasensory Perception (ESP). The psychic was presented with a series of face-down cards and was asked to identify the correct symbol on each card (out of five possible choices). Let pp be the probability that the psychic will correctly identify the symbol on any given card.

If the psychic truly has ESP, then she should be correct more than 20% of the time, meaning p>0.20p>0.20. This hypothesis was tested using a significance level of α=5α=5%.

The P-value for this sample is

If we change the significance level of a hypothesis test from 5% to 2%, which of the following will happen? Check all that apply.

A. The probability of a Type I error increases.
B. It is more likely that we fail to reject the null hypothesis.
C. The probability of a Type II error decreases.
D. The probability of a Type I error decreases.
E. The probability of a Type II error increases.
F. It is less likely that we fail to reject the null hypothesis.
G. It is more likely that the null hypothesis is true.
H. It is more likely that we conclude the null hypothesis is true.

Answer 1

significance level, alpha is the probaiblity type I error
If alpha is decreased from 5% to 2%, probability of type I error decreases.

this also results into the increase in type II error

B. It is more likely that we fail to reject the null hypothesis.

D. The probability of a Type I error decreases.

E. The probability of a Type II error increases.