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One factor in the development of tennis elbow, a malady that strikes fear in the hearts of all serious tennis players, is the impact-induced vibration of the racket-and-arm system at ball contact. It is well known that the likelihood of getting tennis elbow depends on various properties of the racket used. Consider the
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Chapter 12 Solutions
Probability and Statistics for Engineering and the Sciences
- Repeat Example 5 when microphone A receives the sound 4 seconds before microphone B.arrow_forwardResearchers interested in lead exposure due to car exhaust sampled the blood of 52 police officers subjected to constant inhalation of automobile exhaust fumes while working traffic enforcement in a primarily urban environment. The blood samples of these officers had an average lead concentration of 124.32 µg/l and a SD of 37.74 µg/l; a previous study of individuals from a nearby suburb, with no history of exposure, found an average blood level concentration of 35 µg/l. Test the hypothesis that the downtown police officers have a higher lead exposure than the group in the previous study. Interpret your results in context. Based on your preceding result, without performing a calculation, would a 99% confidence interval for the average blood concentration level of police officers contain 35 µg/l? Based on your preceding result, without performing a calculation, would a 99% confidence interval for this difference contain 0? Explain why or why not.arrow_forwardSuppose the table below displays the estimation results from the Logit model Regressor Coefficient (standard error) (log)Income(X1) 0.48 (0.12) Age(X2) 0.03 (0.01) -0.008 (0.02) constant 8.07 (1.16) where the heteroskedasticity-robust standard errors are reported along with the coefficient estimates. How do you interpret the coefficient on log income? Is it significantly different from zero? What is the log odds-ratio for an individual with log income equal to 10 and age equal to 40? Explain what it means.arrow_forward
- a. What is the probability that the lifetime X of the first component exceeds 3? b. What are the marginal pdf's of X and Y? Are the two lifetimes independent? x. What is the probability that the lifetime of at least one component exceeds 3?arrow_forwardA researcher hypothesizes that electrical stimulation of the lateral habenula will result in a decrease in food intake (in this case, chocolate chips) in rats. Rats undergo stereotaxic surgery and an electrode is implanted in the right lateral habenula. Following a ten day recovery period, rats (kept at 80 percent body weight) are tested for the number of chocolate chips consumed during a 10 minute period of time both with and without electrical stimulation. The testing conditions are counter balanced. Compute the appropriate t-test for the data provided below. Stimulation No Stimulation 12 8 7 7 3 4 11 14 8 6 5 7 14 12 7 5 9 5 10 8 a) What would be the null hypothesis and alternative hypothesis in this study? b) What is your tcrit? c) Is there a significant difference between the two groups? d) Interpret your answer. e) Write out your t-value in APA format. *ANSWER ALL PARTS OF THE QUESTION*arrow_forwardA researcher hypothesizes that in a certain country the net annual growth of private sector purchases of government bonds, B, is positively related to the nominal rate of interest on the bonds, NI, and negatively related to the rate of inflation Π: Bt = a0 + a1NIt + a2Π t + ut Note that it may be hypothesized that B depends on the real rate of interest on bonds, R, where R = NI – Π. Using a sample of 56 annual observations, s/he estimates the following equations: (1) Bt = 0.43 + 0.90NIt - 0.97Πt R21 = 0.962, SSR1 = 2.20, QRESET(F1,52) = 16.6 (3.58) (8.80) (-1.05) (2) Bt = 0.44 + 0.94Rt R22 = 0.960, SSR2 = 2.22, QRESET(F1,53) = 0.9 (9.70) (16.7) (3) Bt = 0.44 + 1.14NIt SSR3 = 9.20, QRESET(F1,53) = 59.9 (8.84) (36.1) (4) NIt = 0.08 + 0.94Πt R24 = 0.997, SSR4 = 0.18, QRESET(F1,53) = 1.4…arrow_forward
- Compute the forecasted values for Yt for July and August in 2020 by using the modelsstated in (c) and (d)arrow_forwarda. Compute the incidence rate of coronary artery disease in patients receiving the new cholesterol medication. b. Compute the incidence rate of coronary artery disease in patients receiving a placebo. attached is the image of the data for this problemarrow_forwardA certain training device measures reaction times of users by illuminating lights, one at a time, and measuring the time it takes the user to press each light to turn it off. The makers of the device are marketing it for high-level training, saying that even among professional athletes, the proportion who can score the top ranking of "light speed" is less than 22% . As a fitness trainer who wants to buy the device to attract more customers, you want to feel comfortable that the claim made by the makers is correct. To test the claim, you decide to perform a hypothesis test. To do so, you rent the device and have a random sample of 130 professional athletes use it; 26 score a ranking of "light speed." You confirm that it is appropriate to perform a Z -test. Why is a Z -test appropriate? Find z , the value of the test statistic for your Z -test. Round your answer to three or more decimal places. =zarrow_forward
- For the 23 space shuttle flights before the Challenger mission disaster in 1986, The following table shows the temperature (◦F) at the time of the flight and whether at least one primary O-ring suffered thermal distress. Use logistic regression to model the effect of temperature on the probability of thermal distress. Interpret the effect. Estimate the probability of thermal distress at 31◦F, the temperature at the time of the Challenger flight. At what temperature does the estimated probability equal 0.50? At that temperature, give a linear approximation for the change in the estimated probability per degree increase in temperature. Interpret the effect of temperature on the odds of thermal distress. Test the hypothesis that temperature has no effect, using (i) the Wald test, (ii) the likelihood-ratio test.arrow_forwardIn a recent survey, ice cream truck drivers in Cincinnati, Ohio, reported that they make about $280 in income on a typical summer day. The income was generally higher on days with longer work hours, particularly hot days, and on holidays. The accompanying data file includes five weeks of the driver’s daily income (Income), number of hours on the road (Hours), whether it was a particularly hot day (Hot = 1 if the high temperature was above 85°F, 0 otherwise), and whether it was a Holiday (Holiday = 1, 0 otherwise). Income Hours Hot Holiday 196 5 1 0 282 8 0 0 318 6 1 0 232 5 1 0 276 8 0 0 312 8 0 1 193 5 0 1 110 4 0 0 321 8 1 0 283 8 0 0 325 8 1 0 247 7 0 1 398 8 1 1 448 8 1 1 214 4 0 0 235 8 0 0 238 8 0 0 148 3 1 0 313 8 0 1 449 8 1 1 332 8 1 1 247 8 0 0 363 7 1 0 393 7 1 1 254 8 0 0 228 8 0 0 355 6 1 1 248 7 0 1 291 8 1 0 255 5 1 0 239 6 0 0 181 6 0 0 222 7 0 0 170 5 0 1 374 6 1 1 1. Estimate the effect of…arrow_forward1)A new starch polymer foam with high shock absorbent properties is expected to perform better thanthe old foam which can withstand a maximum impact of 1.56 Joule (J). A simple destructive testto quantify shock absorption ability of the new foam is conducted. Table 5 shows the impact energyabsorbed (in J) that the new foam can withstand for each test. Table 51.61 1.5 1.65 1.7 1.4 1.59 1.65 1.5 Does the recorded data suggests that the new foam performs better than the old foam? Use 2.5%level of significance. 2) A number of 28 university students who smokes completed a questionnaire inquiring their smokinghistory and behavior. The result shows that the average smoking initiation age of this group is 21.6years with a variance of 18.49. Based on past record, the smoking initiation age of universitystudent has a mean of 20.74 years with a standard deviation of 5.1 years. Conduct a necessaryanalysis to determine if the smoking initiation age remain the same as the previous record.…arrow_forward
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw HillTrigonometry (MindTap Course List)TrigonometryISBN:9781337278461Author:Ron LarsonPublisher:Cengage Learning