Explain the reason for the study to be an observational study. Check whether it is possible to conclude that the profitability in companies is due to the internet.

Question

Want to see the full answer?

Answer 1

Question

Chapter 12, Problem 2E

To determine

Explain the reason for the study to be an observational study.

Check whether it is possible to conclude that the profitability in companies is due to the internet.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Students have asked these similar questions

very time you conduct a hypothesis test, there are four possible outcomes of your decision to reject or not reject the null hypothesis: (1) You don’t reject the null hypothesis when it is true, (2) you reject the null hypothesis when it is true, (3) you don’t reject the null hypothesis when it is false, and (4) you reject the null hypothesis when it is false. Consider the following analogy: You are an airport security screener. For every passenger who passes through your security checkpoint, you must decide whether to select the passenger for further screening based on your assessment of whether he or she is carrying a weapon. Suppose your null hypothesis is that the passenger has a weapon. As in hypothesis testing, there are four possible outcomes of your decision: (1) You select the passenger for further inspection when the passenger has a weapon, (2) you allow the passenger to board her flight when the passenger has a weapon, (3) you select the passenger for further inspection when…

EKS C ALEKS - Kim Johnson - Ch 6S × 4 www-awy.aleks.com alekscgi/x/sl.exe/16_u-lgNs/kr7j8FB)--BjuvZG weRMign 4tCy83MpSgONH0-ovaPm-Zym e Chrome isn't your default browser Set as default Ch 6 Sec 4 Homework Question 4 of 4 (1 point) | Question Attempt: 2 of Unlimited ✓ 2 ✓ 3 = 4 Stress at work: In a poll conducted by the General Social Survey, 81% of respondents said that their jobs were sometimes or always stressful. Two hundred workers are chosen at random. Use the TI-84 Plus calculator as needed. Round your answer to at least four decimal places. (a) Approximate the probability that 155 or fewer workers find their jobs stressful. (b) Approximate the probability that more than 145 workers find their jobs stressful. (c) Approximate the probability that the number of workers who find their jobs stressful is between 154 and 172 inclusive. Part 1 of 3 The probability that 155 or fewer workers find their jobs stressful is 0.1207 Part 2 of 3 bility that more than 145 workers find their jobs…

A case-control (or retrospective) study was conducted to investigate a relationship between the colors of helmets worn by motorcycle drivers and whether they are injured or killed in a crash. Results are given in the accompanying table. Using a 0.01 significance level, test the claim that injuries are independent of helmet color. Color of Helmet Black White Yellow Red Blue Controls (not injured) 499 373 32 159 79 Cases (injured 221 108 8 66 38 or killed) Click here to view the chi-square distribution table. Chi-square distribution table Area to the Right of the Critical Value Degrees of Freedom 0.995 0.99 0.975 0.95 0.90 0.10 0.05 0.025 0.01 0.005 C. Ho: Injuries and neimet color are dependent H₁: Injuries and helmet color are independent D. Ho: Whether a crash occurs and helmet color are dependent 1 0.001 0.004 0.016 2.706 3.841 5.024 6.635 7.879 2 0.010 0.020 0.051 0.103 0.211 4.605 5.991 7.378 9.210 10.597 3 0.072 0.115 0.216 0.352 0.584 6.251 7.815 9.348 11.345 12.838 4 0.207 0.297…