Hypothesis testing-confidence interval for cavity prevelance

Reference no: EM13108290

The producers of a new toothpaste claim that it prevents more cavities than other brands of toothepaste. A random of 60 people used the new toothpaste for 6 months. The mean number of cavities at their next check up is 1.5. In the general population, the mean number of cavities at a 6 month checkup is 1.73 (population mean = 1.12).

a. Is this a one or two tail test?

b. What are Ho and Ha for this study?

c. Compare A obt

d. What is Z cv?

e. Should Ho be rejected? What should fhe researcher conclude?

f. Determine the 95% confidence interval for the population mean, based on sample mean.

A researcher believes the percentage of people who exercise in California is greater than the national exercise rate. The national rate is 20%. The researcher gathers a random sample of 120 individuals who live in CA and finds that the number who exercises regularly is 31 out of 120.

a. What is X2 obt?

b. What is the df for this test?

c. What is X cv? What conclusions can be drawn from these results?

Reference no: EM13108290

Questions Cloud

How lengths of cuts on cd to be one thirty two second : CRA CDs Inc. wishes mean lengths of "cuts" on a CD to be 132 seconds (2 minutes and 12 seconds). This will permit disk jockeys to have plenty of time for commercials in each 10-minute segment.

Statistical tests for significance : Show your work (either your hand calculations or your statistical program output). You can either scan your work and submit it as a low-resolution graphic, type your answers directly into the document, or cut and paste your work into a Word file.

Discuss government role with regard to compensation in us : What is government's role with regard to Compensation in the U.S.? How are annual Compensation budgets developed in your company? If you don't know ask your manager or HR person.

Explaining the z test for proportion : A researcher believes that the percentage of people who exercise in California is greater than the national exercise rate. The national rate is 20%.

Hypothesis testing-confidence interval for cavity prevelance : The producers of a new toothpaste claim that it prevents more cavities than other brands of toothepaste. A random of 60 people used the new toothpaste for 6 months.

What is the muler-lyer illusion : What is the muler-lyer illusion? How is this related to psychology.

Hypothesis testing of sprinklers : Sprinkler Systems. A manufacturer of sprinkler systems designed for fire protection claims that the average activating temperature is at least 135 degrees F.

How margin of error associate to confidence interval-ecology : Illustrate how critical values associate to the confidence interval using example variable. Explain how margin of error associates to confidence intervals and to ecology.

Describe economic order quantity technique : What is the Economic Order Quantity technique and what are the basic assumptions the model formula follows? What are some different companies that could benefit from using this type of inventory management and why?

User Account

All Pages