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# Hypothesis Testing

### Number of houses surveyed - Last year trial survey

Last year a trial survey found that 65% of houses in a town had a computer. A follow up survey wants to find the actual number of houses with a computer to within 3% with a 95% confidence interval. How many houses should it survey?

### Calculation of p-value

A coin was flipped 60 times and came up heads 38 times. a) At the 0.10 level of significance, is the coin biased toward heads? Show your decision rule and calculations. b) Calculate the p-value and interpret it.

### Statistics tests of means and proportions

Faced with rising fax costs, a firm issued a guideline that transmissions of 10 pages or more should be sent by 2-day mail instead. Exceptions are allowed, but they want the average to be 10 or below. The firm examined 35 randomly chosen fax transmissions during the next year, yielding a sample mean of 14.44 with a standard devi

### Statistics - Testing Hypothesis (Mean)

The accompanying table shows the grades for three randomly selected samples of students in economics, statistics, and accounting classes. Test the hypothesis that the mean grades are the same for all three classes. Use .05 for the level of significance. Economics(X1 ) Statistics(X2 ) Accounting(X3 ) 80 100 95 90 90 90 70 90 88 1

### Testing Null Hypothesis: Ship Building Company Example

Independent random samples were taken from normal distributions of the yearly production of ships built by the International Ship Building Company under (1) a fixed-position layout and (2) a project layout. The results are given in the accompanying table. Test the null hypothesis that the variance for the fixed-position layout i

### Estimate on Quick brews weekly advertising expenditure

Coffee Times weekly advertising expenditure, Coffee Times weekly advertising expenditure (lagged), Coffee Times price index, Coffee Times price index (Lagged), and Estimate on Quick brews weekly advertising expenditure (lagged). The equation we have developed to predict effects on revenue when one or more of the independent va

### (1) Evolutionary theoies often ... (2) Twenty students ... (Please see the attached file.)

1) Evolutionary theories often emphasize that humans have adapted to their physical environment. One such theory hypothesizes that people should spontaneously follow a ... 2) Twenty students randomly assigned to an experimental group receive an instructional program; 30 in a control group do not. After 6 months, both groups a

### P-value - A coin was flipped 60 times and came up heads ...

A coin was flipped 60 times and came up heads 38 times. (a) At the .10 level of significance, is the coin biased toward heads? Show your decision rule and calculations. (b) Calculate a p-value and interpret it.

### Violation of Guideline: Average patient should pay no more than \$250 out-of-pocket.

An auditor reviewed 25 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was \$275.66 with a standard deviation of \$78.11. (a) At the 5 percent level of significance, does this sample prove a violation of the guideline that the av

### Population means - The Web-based company Oh Baby! Gifts has a goal of processing 95 percent of its orders on the same day ...

The Web-based company Oh Baby! Gifts has a goal of processing 95 percent of its orders on the same day they are received. If 485 out of the next 500 orders are processed on the same day, would this prove that they are exceeding their goal, using &#945; = .025?

### Sample means - Faced with rising fax costs, a firm issued a guideline that transmissions of 10 pages or more should be sent by ...

Faced with rising fax costs, a firm issued a guideline that transmissions of 10 pages or more should be sent by 2-day mail instead. Exceptions are allowed, but they want the average to be 10 or below. The firm examined 35 randomly chosen fax transmissions during the next year, yielding a sample mean of 14.44 with a standard devi

### What are the different types of samples?

What is an independent sample? What is a related sample? When should researchers use different hypothesis tests for independent and related samples? Is one type of sample preferable over the other?

### Test the claim

I went over to our Provost last week to try to convince him that I have the ability of Extrasensory Perception (ESP). I gave him a deck of 10 cards, numbered 1 to 10, and asked him to shuffle them. Then, he would have to look at each card, and concentrate on the number, one at a time. I let him know that I could read hi

### Verbal and Numerical Hypothesis

Formulate a numerical hypothesis of the statement issue. Formulate a verbal hypothesis statement regarding your research issue. The additional information is attached.

### Statistical discussion question - Explain the difference between the null hypothesis and the alternate hypothesis. How is the ...

Explain the difference between the null hypothesis and the alternate hypothesis. How is the null hypothesis chosen (why is it null)? What is the importance of rejecting the null hypothesis in relation of the sample to the population? With a failure to reject the null hypothesis, can we make a general statement about the populati

### Statistics discussion question - Explain the difference between a left tail, two-tailed, and right tailed text. When would we choose ...

Explain the difference between a left tail, two-tailed, and right tailed text. When would we choose a two tailed test? How can we tell the direction by looking at a pair of hypothesis? How can we tell which direction (or no direction) to make the hypothesis by looking at the problem statement (research question)?

### Statistical Symbols and Definitions Matching Assignment

Please see attached file. Statistical Symbols and Definitions Matching Assignment Match the letter of the definition on the right to the appropriate symbol on the left. Symbols Definitions 1. &#61523; (Uppercase Sigma) ____ a. Null hypothesis 2. &#61549; (Mu) ____ b. Summation 3. &#61555; (Lo

### Hypothesis Testing - See attached doc that helps solve the problem.

Perform hypothesis testing on one variable's data. (Choose either the intrinsic or extrinsic column.) Perform a t-test by formulating a null and an alternative statement, choosing an acceptable significance value, determining the appropriate critical value, selecting the test statistic and determining its value from the sample d

### Two sample hypothesis question

10.38 A ski company in Vail owns two ski shops, one on the east side and one on the west side. Sales data showed that at the eastern location there were 56 pairs of large gloves sold out of 304 total pairs sold. At the western location there were 145 pairs of large gloves sold out of 562 total pairs sold. (a) Calculate the s

### Hypothesis Testing

You will be testing the effects of physical activity on happiness ratings for two groups: one group who participates in physical activity and one group who does not participate in physical activity. You will be drawing two samples: one from the population of people who participate in a structured physical activity program and

### Statistics: F Value

Question: What is the critical F value for a sample of four observations in the numerator and seven in the denominator?

### Quantitave Research Methods - 1. NBC TV news, in segment on the price of gasoline, reported last evening that the mean price nationwide is \$2.50 per gallon for self-serve regular unleaded. A random sample of 35 stations in Milwaukee, Wisconsin, area revealed that the mean price was \$2.52 per gallon and that the standard deviation was \$0.05 per gallon. At the .05 significance level, can we conclude that the price of gasoline is higher in the Milwaukee area? Determine the p-value. 2. eGolf.com receives an average of 6.5 returns per day from online shoppers. For a sample of 12 days, it received the following number of returns. 0 4 3 4 9 4 5 9 1 6 7 10 At the .01 significance level, can we conclude the mean number of returns is less than 6.5? 3. Traditionally, two percent of the citizens of the United States live in a foreign country because they are disenchanted with U.S. politics or social attitudes. In order to test if this proportion has increased since the September 11, 2001, terror attack, U.S. consulates contacted a random sample of 400 of these expatriates. The sample yields 12 people who report they are living overseas because of political or social attitudes. Can you conclude this data shows the proportion of political motivated expatriates has increased? Use the 0.05 significance level.

1. NBC TV news, in segment on the price of gasoline, reported last evening that the mean price nationwide is \$2.50 per gallon for self-serve regular unleaded. A random sample of 35 stations in Milwaukee, Wisconsin, area revealed that the mean price was \$2.52 per gallon and that the standard deviation was \$0.05 per gallon. At the

### Hypothesis Testing - Test the hypothesis that the average age of the students in the following group is 35. ... [See the attached question file.]

Test the hypothesis that the average age of the students in the following group is 35. ? Develop a problem statement ? Create the hypothesis, null and alternate based on the problem statement ? Decide on one- or two-tailed test ? Develop the decision criteria, significance level, and critical

### Quantitative Research Methods: Estimating Population Mean

A state meat inspector in Iowa has been given the assignment of estimating the mean net weight of packages of ground chuck labeled "3 pounds." Of course, he realizes that the weights cannot be precisely 3 pounds. A sample of 36 packages reveals the mean weight to be 3.01 pounds, with a standard deviation of 0.03 pounds. a.

### Statistics - Hypothesis Testing Problem of Mortgages

9.58 A sample of 100 mortgages approved during the current year showed that 31 were issued to a single-earner family or individual. The historical average is 25 percent. (a) At the .05 level of significance in a right-tailed test, has the percentage of single-earner or individual mortgages risen? Include a sketch of your decisio

### Perform hypothesis tests on the bottling process and on the hourly wage of secretaries

1. In a bottling process, a manufacturer will lose money if the bottles contain either more or, less than is claimed on the label. The quality manager of a plant is interested in testing whether the mean ounces of catsup per family size bottle differ from the label by amount of 20 ounces. A sample of 9 bottles yields a mean fil

### Hypothesis Test for pi = 0.40.

The following hypotheses are given. H0: pi = .40 H1: pi =/ .40 A sample of 120 observations revealed that p = .30. At the .05 significance level, can the null hypothesis be rejected? a. State the decision rule. b. Compute the value of the test statistic. c. What is your decision regarding the null hypothesis?

### What is the Null Hypothesis?

Discuss: How is the null hypothesis chosen (why is it null)? What is the importance of rejecting the null hypothesis in relation of the sample to the population? With a failure to reject the null hypothesis, can we make a general statement about the population based on the sample findings?

### Hypothesis Testing - How can we tell the direction of the test by looking at a pair of hypothesis? How can we tell which direction (or no direction) to make the hypothesis by looking at the problem statement (research question)?

How can we tell the direction of the test by looking at a pair of hypothesis? How can we tell which direction (or no direction) to make the hypothesis by looking at the problem statement (research question)?

### Hypothesis Test for Measuring Male Egyptian Skulls

The values in the table are measured maximum breaths of male Egyptian skulls from time periods. Changing in head shape over time suggest that interbreading occurred with immigrant populations. Use a 0.05 level significance to test the claim that the different time periods do not all have the same mean. 4000BC 1850BC