A researcher calculates a mean from a sample of 19 people. For α = .05, if the researcher states the hypotheses as H₀: µ = 200 and H₁: µ < 200, which of the following is an appropriate critical value?

A) 0.688
B) 1.645
C) 1.734
D) 1.729

Critical Value

A point on the scale of a test statistic beyond which we reject the null hypothesis, often associated with the desired significance level of a test.

Alpha

A threshold value used in hypothesis testing that defines the probability of making a Type I error, or rejecting a true null hypothesis.