COLLEGE OF THE CANYONs Math 140: Introductory Statistics Instructor: Julio C. He

Question

COLLEGE OF THE CANYONs Math 140: Introductory Statistics Instructor: Julio C. Herrera Exam 5 January 30, 2018 Problem 3: Airline pilots face the risk of progressive hearing loss due to the noisy cockpits of most jet aircraft. Much of the noise comes from air w rather than from the engines. The cockpit noise (in decibels) was measured to the left of the pilots ear on 60 randomly selected flights of one type of aireraft. The computer output below shows the results from a regression model in which the cockpit noise level was predicted by uch of the noise comes from air roar which increases at high speeds the air speed (in mph). Assume the conditions of the linear regression model are satisfied within the range of air speeds tested. Regression Analysis: Noise versus Speed The regression equation is Noise 65.6 0.0734 Speed Predictor Coef SE Coef 95% CI T-Value P-Value Constant 65.624 10,42 44.77 86.47) 6.28 0.000 Speed 0.073417 0.03098 (o.0115, 0.1354) 2.37 0.021 S. 11.4088 R-Sq 8.858 R-Sq (adj) 7.26% = = a. According to the regression line, what is the estimated mean cockpit noise for a plane sitting on the runway, not moving, with its engines running? b. Test the hypothesis that the intercept is 0 using a significance level of 0.05.

Explanation / Answer

3a)
y^ = 65.624 + 0.073417 * x
= 65.624 + 0.073417 *0
= 65.624

b)
p-value for intercept = 0.000 < 0.05
we reject the null and conclude that the intercept is significant

4)a
95% CI = (0.0115,0.1354)
we are 95 % confident that the true slope lies in this confidence interval

b) b) since 0 is not present is confidence interval
speed is significant
hence this interval support the theory yhat cockpit noise is related to air speed

Please rate

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.