A Survey Claims That 9 Out of 10 Doctors Recommend

question 11

Multiple Choice

A survey claims that 9 out of 10 doctors recommend aspirin for their patients with headaches. To test this claim against the alternative that the actual proportion of doctors who recommend aspirin is less than 0.90, a random sample of 100 doctors was selected. Suppose that the test statistic is -2.20. Can you conclude that H₀ should be rejected at the (a) α = 0.10, ?(b) α = 0.05, and (c) α = 0.01 level of Type I error?

• A) (a) yes; (b) yes; (c) yes
• B) (a) no; (b) no; (c) no
• C) (a) no; (b) no; (c) yes
• D) (a) yes; (b) yes; (c) no

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Definitions:

Critical Value

A point on the test distribution that is compared with the test statistic to determine whether to reject the null hypothesis.

Alpha

The level of significance in statistical testing, representing the probability of rejecting the null hypothesis when it is actually true.

Standard Error

A statistical measure that estimates the accuracy with which a sample distribution represents a population by using standard deviation and sample size.

Significance Level

A threshold in hypothesis testing that determines whether an observed effect is statistically significant.