Question

Dentists make many people nervous. To see whether such nervousness elevates blood pressure, the blood pressure and pulse rates of 60 subjects were measured in a dental setting and in a medical setting. For each subject, the difference (dental-setting blood pressure minus medical-setting blood pressure) was calculated. The analogous differences were also calculated for pulse rates. Summary data are given below.

	Mean Difference	Standard Deviation of Differences
Systolic Blood Pressure	4.49	8.77
Pulse (beats/min)	−1.33	8.84

(a)

Do the data strongly suggest that true mean blood pressure is greater in a dental setting than in a medical setting? Use a level 0.01 test. (Use a statistical computer package to calculate the P-value. Round your test statistic to two decimal places, your df down to the nearest whole number, and your P-value to three decimal places.)

t=

df=

P-value=

State your conclusion.

We reject H₀. We do not have convincing evidence that the mean blood pressure is greater in a dental setting than in a medical setting.

We do not reject H₀. We have convincing evidence that the mean blood pressure is greater in a dental setting than in a medical setting.    

We reject H₀. We have convincing evidence that the mean blood pressure is greater in a dental setting than in a medical setting.

We do not reject H₀. We do not have convincing evidence that the mean blood pressure is greater in a dental setting than in a medical setting.

(b)

Is there sufficient evidence to indicate that true mean pulse rate in a dental setting differs from the true mean pulse rate in a medical setting? Use a significance level of 0.05. (Use a statistical computer package to calculate the P-value. Round your test statistic to two decimal places, your df down to the nearest whole number, and your P-value to three decimal places.)

t=

df=

P-value=

State your conclusion.

We do not reject H₀. We have convincing evidence that the mean pulse rate in a dental setting differs from the mean pulse rate in a medical setting.

We reject H₀. We do not have convincing evidence that the mean pulse rate in a dental setting differs from the mean pulse rate in a medical setting.    

We do not reject H₀. We do not have convincing evidence that the mean pulse rate in a dental setting differs from the mean pulse rate in a medical setting.

We reject H₀. We have convincing evidence that the mean pulse rate in a dental setting differs from the mean pulse rate in a medical setting.

Answer 1