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Hypothesis Testing

Description of Statistics - Hypothesis Testing

1. Consider the following hypothesis test: Ho: u</= 12 Ha: u>12 A sample of 25 provided a sample mean x=14 and a sample standard deviation s = 4.32 a. Compute the test statistic. b. Use the t distribution table to compute a range for the p value c. At alpha= 0.05, what is the conclusion. d. What is the rejection rule us

Hypothesis Testing - 22. Car manufacturers have to publish an estimated MPG for each model production. Prior to manufacturing "Car A" the manufacturer stated that the MPG. ... [Please see the attached questions file.]

22. Car manufacturers have to publish an estimated MPG for each model production. Prior to manufacturing "Car A" the manufacturer stated that the MPG. ... 25. A group of University of Florida psychologist investigated the effects of age and gender on the short-term memory of adults ... 26. The Time/CNN survey, 24% if 205 s

Statistics: Flights at O'Hare, FAX costs & Coin Flipping

22 The mean arrival rate of flights at O'Hare Airport in marginal weather is 195 flights per hour with a historical standard deviation of 13 flights. To increase arrivals, a new air traffic control procedure is implemented. In the next 30 days of marginal weather the mean arrival rate is 200 flights per hour. (a) Set up a rig

Hypothesis Testing in Excel

Please use Excel to solve the statistics problem. The MBA department is concerned that dual degree students may be receiving lower grades than the regular MBA students. Two independent random samples have been selected. 100 observations from population 1 (dual degree students) and 100 from population 2 (MBA students). The sam

SPSS: Employees and Revenue Large Automotive Companies

Please see attached. Data Set "B" is on last page. Choose the dependent variable (the response variable to be "explained") and the independent variable (the predictor or explanatory variable) as you judge appropriate. Use a spreadsheet or a statistical package (e.g., MegaStat or MINITAB) to obtain the bivariate regression and r

Hypothesis Testing Given n = 28

Given n = 28; σ = 0.7; = 5.7; and α = 0.01; Test Ho: µ = 6 against Ha: μ and ≠ 6.

To test the hypothesis that students who finish an exam first get better grades, Professor Hardtack kept track of the order in which papers were handed in. The first 25 papers showed a mean score of 77.1 with a standard deviation of 19.6, while the last 24 papers handed in showed a mean score of 69.3 with a standard deviation of

Grade Point Average Variances at a 0.05 Level of Significance

Assuming that the population variances are equal for male and female Grade Point Averages (GPAs), use the following sample data to test whether the averages are different at the 0.05 level of significance. Male GPA's Female GPA's Sample Size 17 15 Sample Mean 3.8 3.9

One-tailed hypothesis: A certain brand of fluorescent light tube was advertised as having an average illumination life-span of 2,000 hours. A random sample of 64 bulbs burned out with a mean life-span of 1,970 hours and a sample standard deviation of 80 hours. With a 0.05 level of significance, is the sample mean less than the advertised mean?

A certain brand of fluorescent light tube was advertised as having an average illumination life-span of 2,000 hours. A random sample of 64 bulbs burned out with a mean life-span of 1,970 hours and a sample standard deviation of 80 hours. With a 0.05 level of significance, is the sample mean less than the advertised mean?

Normality and Hypothesis Testing

1. R.C. Geary wrote some 70 years ago that "Normality is a myth. There never was, is, nor will there ever be a Normal distribution". What do you think he meant and what relevance does it have to your work?(Read the Week 2 Lecture 1 before answering) 2.How do you feel that the inferential statistical technique of Hypothesis T

Hypothesis Testing for Male and Female Grade Point Averages

Assuming that the population variances are equal for male and female Grade Point Averages (GPAs), use the following sample data to test whether the averages are different at the 0.05 level of significance. Male GPA's Female GPA's Sample Size 17

Hypothesis testing for proportions

A test was conducted to determine whether gender of a spokesperson affected the likelihood that consumers would prefer a new product. A survey of consumers at a trade show employing a female spokesperson determined that 60 out of 200 customers preferred the product, while 72 of 180 customers preferred the product when a male sp

Hypothesis Testing: Comparing Sample Means

Given the following data from two independent samples, conduct a one-tailed hypothesis test to determine if the first sample mean is larger than the second sample mean, given a 0.05 level of significance. n1 =45 n2 = 36 xbar1=64 xbar2 = 60 s1=15 s2 = 12

One-Tailed Hypothesis Testing for Fluorescent Light Tubes

Conduct a one-tailed hypothesis test given the information below. A certain brand of fluorescent light tube was advertised as having an average illumination life-span of 2,000 hours. A random sample of 64 bulbs burned out with a mean life-span of 1,970 hours and a sample standard deviation of 80 hours. With a 0.05 level of

Please solve the following problem using the 5 step procedure for hypothesis testing. A sample of 25 concession stand purchases at the October 22 matinee of Bride of Chucky showed a mean purchase of \$5.29 with a standard deviation of \$3.02. For the October 26 evening showing of the same movie, for a sample of 25 purchases the

Statistics in business - To test the hypothesis that students who finish an exam first get better grades, Professor Hardtack kept track of the order in which papers were handed in. The first 25 papers showed a mean score of 77.1 with a standard deviation of 19.6, while the last 24 papers handed in showed a mean score of 69.3 with a standard deviation of 24.9. Is this a significant difference at &#945; = .05? ...

Please solve the following problem using the 5 step procedure for hypothesis testing. To test the hypothesis that students who finish an exam first get better grades, Professor Hardtack kept track of the order in which papers were handed in. The first 25 papers showed a mean score of 77.1 with a standard deviation of 19.6,

Please solve the problem using the 5 step procedure for hypothesis testing. In a Texas study,researchers gave lovastatin to 2,325 people and an inactive substitute to 2,081 people (average age 58). After 5 years, 57 of the lovastatin group had suffered a heart attack, compared with 97 for the inactive pill. (a) State the

Group test for means

Jerry's Bargain Department Store spent \$50,000 on a training program to improve sales effectiveness of its employees. Below is a table of the before and after sales amounts for a random sample of employees who took the training program. Assume that data is recorded for an equal period of "before"-"after" time. Use the 1% leve

Hypothesis Testing

A manufacturer of hard hats for construction workers is concerned about the mean and the variation of the forces its helmets transmit to wearers when subjected to a standard external force. The manufacturer desires the mean force transmitted by helmets to be 800 pounds (or less), well under the legal 1000-pound limit, and desir

Hypothesis Testing - Product Sales Distribution

For the following problems follow these steps a state the hypotheses and identify the claim b find the critical value(s) c compute the test value d make the decision e summarize the results Product sales distribution A company owner wishes to determine whether the number of sales o

Hypothesis Testing - Height of Baseball Players

Heights of baseball players A researcher wants to compare variances of heights in inches of major league players with those in the minor league baseball a sample 25 players from each league variances for heights of each league are 2.25 and 4.85 respectively. At α = 0.10, is there a significant difference between the varian

Variation in processing times

A computer manufacturer is about to unveil a new, faster personal computer. The new machine clearly is faster, but initial tests indicate there is more variation in the processing time. The processing time depends on the particular program being run, the amount of input data, and the amount of output. A sample of 16 computer run

Statistics - Probability - Hypothesis Testing

The Telecommunications industry achieved a more rapid increase in ROI during its initial 75 years in existence than the Oil & Gas industry achieved. Which business sector, Oil & Gas or Telecommunications, achieved the greater ROI as their relative business sector matured?" Assuming level of significance &#945;= .05 3. Cal

Statistics - Hypothesis Testing Problem

Please help with the following problem. There are two Chevrolet dealers in Jamestown, New York. The mean weekly sales at Sharkey Chevy and Dave White Chevrolet are about the same. However, Tom Sharkey, the owner of Sharkey Chevy, believes his sales are more consistent. Below is the number of new cars sold at Sharkey in the l

Hypothesis Testing for Variation in Processing Time

A computer manufacturer is about to unveil a new, faster personal computer. The new machine clearly is faster, but initial tests indicate there is more variation in the processing time. The processing time depends on the particular program being run, the amount of input data, and the amount of output. A sample of 16 computer run

Current-Period Income Effect- Four Earnings Management Approaches

In a study of how managers attempt to manage earnings, researchers analyzed a sample of 515 earnings- management attempts from a survey of experienced auditors. The frequency of effects is summarized in the table shown. Research question: At α = .01, is the effect on earnings independent of the approach used? Current-Perio

ANOVA - Comparing Mid Size Automobiles

A well-known automotive magazine took three top of the line mid size automobiles manufactured in the United States, test-drove them, and compared them on a variety of criteria. In the area of gasoline mileage performance, five automobiles of each brand were each test-driven 500 miles; the miles per gallon data obtained follow. U

A large candy manufacturer is concerned that the mean weight of their Chunky Chocolate Crisp bar is not greater than 4.3 ounces. It can be assumed that the population standard deviation is .03 ounces based on past experience. A sample of 100 candy bars is selected and the sample mean is 4.34 ounces. Using a level of significance of .10, is there evidence that the population mean weight of the candy bars is greater than 4.3? Fully explain your answer.

Please use Excel to solve the statistics problem. It is EXTREMELY important that you use EXCEL and prepare a written discussion of problem to accompany the numerical calculations. You should attach the Excel file. A large candy manufacturer is concerned that the mean weight of their Chunky Chocolate Crisp bar is not greater t

Test statistics/directional research hypothesis

An entrepreneur owns two hotels, one in the western region of a certain state and the other in the eastern region. He thinks that the average amount spent by guests for lunch at his Friendly Café-West is less than \$34.50, the average amount spent for lunch by guests at his similar Friendly Café-East. A random sample of 100 l