According to a large oil company, the average cost per barrel of oil last year was $47. You believe that due to the current oil crisis in Russia and Iran that the cost of a barrel of oil has decreased. You collect a simple random sample of 60 barrels of oil and find an average price of $42 and a standard deviation of $12. Use this information to answer the following questions and conduct the hypothesis test with a level of significance of a = .01. You may use Statcrunch or a calculator. Write all non-calculation answers in complete sentences. a. Which test would you use and why? b. Write the null and alternative hypothesis in complete sentences. (Make sure you mark which is the null and which is the alternative.) c. Write the null and alternative hypothesis as symbols. d. State the requirements that have been met to run the test. e. What is the test statistic and the p-value? (Make sure you use the right notation.) f. Should you reject or fail to reject the null hypothesis? g. State the conclusion for the test. h. According to your findings, has the price of oil decreased? Explain your reasoning based

According to a large oil company, the average cost per barrel of oil last year was $47. You believe that due to the current oil crisis in Russia and Iran that the cost of a barrel of oil has decreased. You collect a simple random sample of 60 barrels of oil and find an average price of $42 and a standard deviation of $12. Use this information to answer the following questions and conduct the hypothesis test with a level of significance of a = .01. You may use Statcrunch or a calculator. Write all non-calculation answers in complete sentences. a. Which test would you use and why? b. Write the null and alternative hypothesis in complete sentences. (Make sure you mark which is the null and which is the alternative.) c. Write the null and alternative hypothesis as symbols. d. State the requirements that have been met to run the test. e. What is the test statistic and the p-value? (Make sure you use the right notation.) f. Should you reject or fail to reject the null hypothesis? g. State the conclusion for the test. h. According to your findings, has the price of oil decreased? Explain your reasoning based

MATLAB: An Introduction with Applications

6th Edition

ISBN:9781119256830

Author:Amos Gilat

Publisher:Amos Gilat

Chapter1: Starting With Matlab

Section: Chapter Questions

Problem 1P

See similar textbooks

Similar questions

Many cheeses are produced in the shape of a wheel. Because of the differences in consistency between these different types of cheese, the amount of cheese, measured by weight, varies from wheel to wheel. Heidi Cembert wishes to determine whether there is a significant difference, at the 10% level, between the weight per wheel of Gouda and Brie cheese. She randomly samples 18 wheels of Gouda and finds the mean is 1.3 lb with a standard deviation of 0.3 lb; she then randomly samples 10 wheels of Brie and finds a mean of 0.95 lb and a standard deviation of 0.21 lb. What is the df and p-value for Heidi's hypothesis of equality? Assume normality. (Give your answer correct to four decimal places.)
State the null and alternative hypotheses. John, a restaurant owner, suspects that prices of tomatoes in Bury are higher than the rest of Manchester. He finds that the city average price of a certain type of premium tomatoes is £20.9 with standard deviation £0.95. He takes a sample of this type of tomato from 5 local Bury stores and obtains an average price of £22.46.
You are a manager of a building that hosts the local farmers market for a town. You want to investigate if the average amount of sales for a vendor per week at your building is greater than $2040. After surveying 17 of their vendors, you find that mean sales per week of the vendors sampled was $2110 with a standard deviation of $114.03. What is the value of the test statistic for your hypothesis test? Note: 1- Only round your final answer. Round your final answer to two decimal places.
The average American consumes 89 liters of alcohol per year. Does the average college student consume less alcohol per year? A researcher surveyed 15 randomly selected college students and found that they averaged 87.3 liters of alcohol consumed per year with a standard deviation of 15 liters. What can be concluded at the the a = 0.05 level of significance? a. For this study, we should use Select an answer b. The null and alternative hypotheses would be: Но: ? Select an answer V Н: ? v Select an answer V c. The test statistic ? v = (please show your answer to 3 decimal places.) d. The p-value = (Please show your answer to 4 decimal places.) e. The p-value is ? v a f. Based on this, we should Select an answer g. Thus, the final conclusion is that ... the null hypothesis. O The data suggest the population mean is not significantly less than 89 at a = 0.05, so there is statistically insignificant evidence to conclude that the population mean amount of alcohol consumed by college students…
Choose the appropriate statistical test. When computing, be sure to round each answer as indicated. A dentist wonders if depression affects ratings of tooth pain. In the general population, using a scale of 1-10 with higher values indicating more pain, the average pain rating for patients with toothaches is 6.8. A sample of 30 patients that show high levels of depression have an average pain rating of 7.1 (variance 0.8). What should the dentist determine? 1. Calculate the estimated standard error. (round to 3 decimals). [st.error] 2. What is thet-obtained? (round to 3 decimals). 3. What is the t-cv? (exact value) 4. What is your conclusion? Only type "Reject" or Retain"
We want to conduct a hypothesis test of the claim that for middle-aged adults the population's mean of their cholesterol levels is more than 199.3 mgdL. We choose a random sample of such levels. The sample has a mean of 197.3 mgdL and a standard deviation of 19.5 mgdL. For each of the following sampling scenarios, choose an appropriate test statistic for our hypothesis test on the population mean. Then calculate that statistic. Round your answers to two decimal places. (a) The sample has size 105, and it is from a non-normally distributed population with a known standard deviation of 19.2. z = t = It is unclear which test statistic to use. (b) The sample has size 12, and it is from a normally distributed population with an unknown standard deviation. z = t = It is unclear which test statistic to use.
Americans are about 1 inch taller but nearly 25 pounds heavier than in 1960. The average BMI increased from approximately 25 to 28 in 2002. Boston is considered one of americas healthiest cities. Is the weight gain since 1960 similar in boston? Sample of n=25 and mean increase of 17 with standard deviation of 8.6. Is boston statistically significantly different in terms of weight gain since 1960? Run the appropriate test at 5%level of significance. A.state the null and the research hypotheses, b. Idebtify critical values of z 9r t used to define the decision rule, c. Calculate the test statistic, d. Report the p-value, e. Report your findings
Solve for all parts of the following question, please.
You are a manager of a building that hosts the local farmers market for a town. You want to investigate if the average amount of sales for a vendor per week at your building is greater than $2050. After surveying 18 of their vendors, you find that mean sales per week of the vendors sampled was $2100 with a standard deviation of $101.08. What is the value of the test statistic for your hypothesis test? Note: 1- Only round your final answer. Round your final answer to two decimal places.
Your answer is partially correct. According to the U.S. Bureau of Labor Statistics, all workers in America who had a bachelor's degree and were employed earned an average of $1233 a week in 2014. A recent sample of 388 American workers who have a bachelor's degree showed that they earn an average of $1240 per week. Suppose that the population standard deviation of such earnings is $137. a. Find the p-value for the test of hypothesis with the alternative hypothesis that the current mean weekly earning of American workers who have a bachelor's degree is higher than $1233. Will you reject the null hypothesis at a = 0.005? Round your answer to four decimal places. p-value = i 0.8264 Do not reject Z = b. Test the hypothesis of part a using the critical-value approach and a = 0.005. Ho. Round your answer for the observed value of z to three decimal places. i 0.94