Hypothesis testing using samples

Assignment Help Basic Statistics

Reference no: EM13108867

Problem 1:

A study by Hewitt Associates showed that 79% of companies offer employees flexible scheduling. Suppose a researcher believes that in accounting firms this figure is lower. The researcher randomly selects 415 accounting firms and through interviews determines that 303 of these firms have flexible scheduling. With a 1% level of significance, does the test show enough evidence to conclude that a significatly lower proportion of accounting firms offer employees flexible scheduling.

Problem 2:

A previous experience shows the variance of a given process to be 14. Researchers are testing to determine whether this value has changed. They gather the following dozen measurements of the process. Use these data and a significance level of .05 to test the null hypothesis about the variance. Assume the measurements are normally distributed.

52 44 51 58 48 49

38 49 50 42 55 51

Problem 3:

Highway engineers in Ohio are painting white stripes on a highway. The stripes are supposed to be approximately 10 feet long. However, because of the machine, the operator, and the motion of the vehicle carrying the equipment, considerable variation occurs among the stripe lengths. Engineers claim that the variance of stripes is not more than 16 inches. Use the sample lengths given here from 12 measured stripes to test the variance claim. Assume stripe length is normally distributed. Let the significance level = .05

Stripe Lengths in Feet

10.3 9.4 9.8 10.1

9.2 10.4 10.7 9.9

9.3 9.8 10.5 10.4

Reference no: EM13108867

Questions Cloud

Alternative hypothesis for a null hypothesis : What is the alternative hypothesis for a null hypothesis stating that the average time a person keeps a cell phone is, at most, three years?

How many grams of mgso4 would you need : If you wanted to make a 0.5M solution of MgSO4, how many grams of MgSO4 would you need? Assume the volume of the solution is one liter. Show your work.

Find out a confidence interval for the true mean lifetime : Find out a 90% confidence interval for the true mean lifetime of all light bulbs of this brand. Then complete the table below. Carry your intermediate computations to at least three decimal places. Round your answers to one decimal place.

Determine the molar mass of the nonelectrolyte : Determine the molar mass of the nonelectrolyte if the osmotic pressure of the solution = 23.6 atm, also express your answerin g/mol?

Hypothesis testing using samples : A study by Hewitt Associates showed that 79% of companies offer employees flexible scheduling. Suppose a researcher believes that in accounting firms this figure is lower.

Explain the black x pink tail and black x black crosses : In rats, a black-tailed mutant was discovered. When it was crossed to a pink long-tailed rat, 4 offspring were black-tailed and 3 were pink tailed. Two of these black-tailed rats were crossed and they produce 6 black tailed and 3 pink-tailed rats.

Determine the new volume of balloon : Determine the new volume of a 1.3 L balloon if it is taken from room temperature that is twenty five degree celsius and placed into a freezer at the temperature of -11.5 degree celsius.?

Which one of those components will break down : When you eat a salad with lettuce, croutons, hard-boiled egg, bacon bits, and salad dressing, which one of those components will break down the least as it passes through your digestive system? Why?

Illustrate what is the maturity risk premium for the year : The real risk free rate is 3% pand inflation is expected to be 3% for the next 2 years. A 2 year Treasury security yields 6.2 %. Illustrate what is the Maturity risk premium for the 2 year security?

User Account

All Pages