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Hypothesis Testing

Hypothesis Test on population proprotion

Tourism is one consideration for CoffeeTime's future, A survey of 1,233 visitors to mumbai last year revealed that 110 visited a small cafe during their visit. Laura claims that 10% of tourists will include a visit to a cafe.

Statistics Review - Significance Level, P-Value

1. A financial analyst wants to compare the turnover rates, in percent, for shares of oil-related stocks versus other stocks, such as GE and IBM. She selected 32 oil-related stocks and 49 other stocks. The mean turnover rate of oil-related stocks is 31.4 percent and the standard deviation 5.1 percent. For the other stocks, the m

Statistics Review Problem Set

1. The following is a hypothetical set of anxiety scale scores from a population of students being seen at a college counseling center: 5 16 47 6 18 50 9 25 50 10 46 50 12 47 78 What are the Z and the T scores of the person who scored 6? 18? Of the two people who scored 47? Of the person who scored 78? Why is it not a

Statistic Mean and Sampling

Clark Heter is an industrial engineer at Lyons Products. He would like to determine whether there are more units produced on the afternoon shift than on the day shift. A sample of 54 day-shift workers showed that the mean number of units produced was 345, with a standard deviation of 21. A sample of 60 afternoon-shift workers sh

Hypothesis Testing - Highschool Smoking

2) In 1999 the Center of Disease Control estimated that about 34.8% of high-school students smoked cigarettes. They established a national health goal of reducing that figure to 16% by the year 2010. To that end, they hoped to achieve a reduction to 30% by the end of 2001. Early in 2002 they released a research study in which on

Statistics Data Help

I am doing a project where I am comparing the accuracy and reproducibility of 3 different force gauges with varied angles and applied pressures. All of the gauges have a 50 lb. capacity. They will all be tested with 0-30 lbs in 5 lb increments of applied load/pressure. They will also be tested at 0 degrees (true perpendicular)

Hypothesis test

For a number of years... In the first year after the change, there were 56- survivors in a class of 800. Is this increase explainable as simply sampling variability? Test at a=0.01. Please see attached.

Hypothesis test

Seven skulls... Use these statistics in a test of the hypothesis that these skulls belong to a race previously found nearby in which the average width if known to be 146mm. Assume a nearly normal population. Perform the test a=0.1. Please see attached.

Statistics - Baseball Team Scores

Perform each of the steps below using Excel. Use the collected data from the chart (MLB Statistics) as a sample of the population (Any one statistic you choose). Describe the population that the data represents. Interpret each of your results with a conclusion and decision. Use any statistic on the MLB chart to answer the questi

Hypothesis Testing, Mean and Standard Deviation

26. To obtain information on the corrosion-resistance properties of a certain type of steel conduit, 45 specimens are buried in soil for a 2-year period. The maximum penetration (in mils) for each specimen is then measured, yielding a sample average penetration of x-bar= 52.7 and a sample standard deviation of s = 4.8. The condu

Statistics Questions

Does correlation equal causation? Why or why not? What is the relationship between correlation and association? What is association? When would you use regression correlation at your place of employment, in your education, or in politics? How do you identify outliers in your data? What are the differences between

Using AIU's large data base of survey responses from unit 2 Individual project (keep in mind this data base is your sample), you will begin testing hypothesis. Complete all of the following:

Using AIU's large data base of survey responses from unit 2 Individual project (keep in mind this data base is your sample), you will begin testing hypothesis. Complete all of the following: 1. Test a hypothesis to see whether the average overall job satisfaction (in the population of all workers in the USA) is equal to 4.5=.

5 Step Hypothesis Testing Procedure

Ms Lisa is the budget director for the New Process Company. She would like to compare the daily travel expenses for the sales staff and the audit staff. She collected the following sample info: Sales ($) 131 135 146 165 136 142 Audit ($) 130 102 129 143 149 120 139 At the .10 confidence level, canshe conclude that the mea

Solve: Hypothesis Testing

Scenario: Your company must make a decision about a very large investment. An internal study shows that if demand for your product increases substantially from the current levels, new production lines must be set up to meet the demand at a reasonable cost and an acceptable quality level. Trying to meet the demand with current fa

Performing Hypothesis Testing

Using a hypothesis test with a well known 4 step procedure, state your conclusion for the 0.05 significance level: A. Based on responses from 1,015 randomly selected teens, which concluded that 44% of teens say grades are the greatest source of pressure, test the claim that fewer than half of all teens in the population feel

Prenatal alcohol hypothesis testing

Alcohol appears to be involved in a variety of birth defects, including low birth weight and retarded growth. A researcher would like to investigate the effect of prenatal alcohol on birth weight. A random sample of n=16 pregnancy rates is obtained. The mother rats are given daily doses of alcohol. The average weight for the sam

Null Hypothesis Statistics

Question: A researcher is using a sample for n=16 lab rats to examine the effect of a new diet drug. It's known that under regular circumstances these rats eat an average of 10 grams of food each day. The distribution of food consumption is normal with a standard deviation=4. The expected effect for the drug is to reduce food co

Statistical Significance

Your car gets 29 miles per gallon, one day you see your mileage average is 28 miles per gallon. Is this change statistically significantly and would you look for a reason or is it more of a variation attributed to chance? Another day you see your mileage is 22 miles per gallon - Is this change statistically significantly and

Is there a difference in proportion?

10. The manager of a computer software company wishes to study the number of hours top executives spend at their computer terminals by type of industry. The manager selected a sample of five executives from each of three industries. At the .05 significance level, can she conclude there is a difference in the mean number of hours

Statistics : Hypothesis Testing, Test Statistic and Critical Region

Please help answer the following questions involving statistics. 1. Why do we use hypothesis testing? 2. What is a test statistic and how is it related to a critical value in hypothesis testing? 3. What is the critical region in hypothesis testing and why is it important?