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# Hypothesis Testing

### Hypothesis Testing of Mean: Chronic Fatigue Syndrome

Patients with Chronic Fatigue Syndrome were tested, and then retested after being treated with fludrocortisone. The changes in fatigue after treatment were measured (based on data from "The Relationship between Neurally Mediated Hypotension and the Chronic Fatigue Syndrome" by Bou-Holaigah, Rowe, Kan, and Calkins, Journal of the

### Hypothesis Testing of Mean: Evidence that executive blood pressures differ from the national average

Do middle-aged male executives have different average blood pressure than the general population? The National Center for Health Statistics reports that the mean systolic pressure for males ages 35 to 44 is 128 and the standard deviation of this population is 15. The medical director of a company looks at the medical records of

### Test four colors of sticky boards in a field of oats to trap beetles

The presence of harmful insects in farm fields is detected by erecting boards covered with a sticky substance and then examining the insects trapped on the board. To investigate which colors are most attractive to cereal leaf beetles, researchers placed six boards of each of four colors in a field of oats. The data is listed bel

### Statistics

The Computer Anxiety Rating Scale (CARS) measures an individual's level of computer anxiety, on a scale from 20 ( no anxiety) to 100 (highest level of anxiety). Researchers at Miami University administered CARS to 172 business students. One of the objectives of the study was to determine whether there is a difference between th

### Critical Value, Calculated Value, and P-Value

See the attached file. A national sales manager of an automobile supply chain claims that monthly sales of auto parts at on of the district office are an average of \$5,285. The district manager believes the amount is too high. They authorize you to settle the dispute. You take a simple random sample (n=25) of the sales receip

### Hypothesis testing : T test.

32. What probability value would be needed to complete the following probability distribution? x -5 -1 0 1 4 P(x) 0.13 0.25 0.12 0.30 25. An apartment building has the following apartments: 1 bedroom 2 bedroom 3 bedroom 1st floor 3 1 1 2nd floor 2 2 2 3rd floor 1 4 1 If an apartment is selected at random, what is

### Levels of Measurement in Statistics

How do you classify statistical findings in order of power: nominal, ordinal, interval, and ratio? Give example by making up values. Use example of Rancidity values in Rice Bran. Thanks

### Statistics

31. A new weight-watching company, Weight Reducers International, advertises that those who join will lose, on the average, 10 pounds the first two weeks with a standard deviation of 2.8 pounds. A random sample of 50 people who joined the new weight reduction program revealed the mean loss to be 9 pounds. At the .05 level of

### Test length of Major League Baseball games

MegaStat > Hypothesis Tests During recent seasons, Major League Baseball has been criticized for the length of the games. A report indicated that the average game lasts 3 hours and 30 minutes. A sample of 17 games revealed the following times to completion. (Note that the minutes have been changed to fractions of hours, so th

### Statistics: T distribution, freshman in training program, effects of humidity on eating

4. Explain why a t distribution tends to be flatter and more spread out than the normal distribution. 12. Last fall a sample of n = 36 freshman was selected to participate in a new four hour training program designed to improve study skills. To evaluate the effectiveness of the new program, the sample was compared with t

### Thirty anorexic girls were treated with cognitive behavioral therapy (CBT). They were weighed before and after the treatment. The weight gains, which are positive scores, and weight losses, which are negative scores, are given below. A gain of more than zero pounds would confirm whether the treatment worked. Did the group gain more than zero pounds? Data: 1.7 0.7 -0.1 -0.7 -3.5 14.9 3.5 17.1 -7.6 1.6 11.7 6.1 1.1 -4.0 20.9 -9.1 2.1 -1.4 1.4 -0.3 -3.7 -0.8 2.4 12.6 1.9 3.9 0.1 15.4 -0.7 0 Report the appropriate null and research hypotheses and the critical value (alpha = 0.05). In addition, provide your statistical conclusion, including calculation of test statistic, in the APA format and conceptual conclusion in one to two sentences.

Thirty anorexic girls were treated with cognitive behavioral therapy (CBT). They were weighed before and after the treatment. The weight gains, which are positive scores, and weight losses, which are negative scores, are given below. A gain of more than zero pounds would confirm whether the treatment worked. Did the group gain m

### Describe under what circumstances a parametric test is not applicable and a nonparametric test has to be done

Describe under what circumstances a parametric test is not applicable and a nonparametric test has to be done.

### Null and alternative hypothesis for St. Luke's Hospital post anaesthesia care area

The post anaesthesia care area (recovery room) at St. Luke's Hospital in Pflugerville, Ontario, was recently enlarged. The hope was that with the enlargement the mean number of patients per day would be more than 25. A random sample of 15 days from an approximately normal population revealed the following numbers of patients:

### Statistics Problems: T-value, Z-value and Null Hypothesis

1. A random sample of size 81 is taken from a large population, measuring the time it takes to complete a driver's license examination. The sample mean was found to be 43 minutes, and the sample standard deviation 5.71 minutes. Construct a 95% confidence interval around the sample mean. Be sure to show whether you use the t- or

### There are four entrances to the Government Center Building in downtown Philadelphia. The building maintenance supervisor would like to know if the entrances are equally utilized. To investigate, 400 people were observed entering the building. The number using each entrance is reported below. At the .01 significance level, is there a difference in the use of the four entrances? Entrance Frequency Main Street 140 Broad Street 120 Cherry Street 90 Walnut Street 50 Total 400 Show step-by-step solution.

20. There are four entrances to the Government Center Building in downtown Philadelphia. The building maintenance supervisor would like to know if the entrances are equally utilized. To investigate, 400 people were observed entering the building. The number using each entrance is reported below. At the .01 significance level, is

### In a particular market there are three commercial television stations, each with its own evening news program from 6:00 to 6:30 P.M. According to a report in this morning's local newspaper, a random sample of 150 viewers last night revealed 53 watched the news on WNAE (channel 5), 64 watched on WRRN (channel 11), and 33 on WSPD (channel 13). At the .05 significance level, is there a difference in the proportion of viewers watching the three channels? Show step-by-step solution.

In a particular market there are three commercial television stations, each with its own evening news program from 6:00 to 6:30 P.M. According to a report in this morning's local newspaper, a random sample of 150 viewers last night revealed 53 watched the news on WNAE (channel 5), 64 watched on WRRN (channel 11), and 33 on WSPD

### A real estate agent in the coastal area of Georgia wants to compare the variation in the selling price of homes on the oceanfront with those one to three blocks from the ocean. A sample of 21 oceanfront homes sold within the last year revealed the standard deviation of the selling prices was \$45,600. A sample of 18 homes, also sold within the last year, that were one to three blocks from the ocean revealed that the standard deviation was \$21,330. At the .01 significance level, can we conclude that there is more variation in the selling prices of the oceanfront homes? Show a step-by-step solution.

A real estate agent in the coastal area of Georgia wants to compare the variation in the selling price of homes on the oceanfront with those one to three blocks from the ocean. A sample of 21 oceanfront homes sold within the last year revealed the standard deviation of the selling prices was \$45,600. A sample of 18 homes, also s

### The president of the American Insurance Institute wants to compare the yearly costs of auto insurance offered by two leading companies. He selects a sample of 15 families, some with only a single insured driver, others with several teenage drivers, and pays each family a stipend to contact the two companies and ask for a price quote. To make the data comparable, certain features, such as the deductible amount and limits of liability, are standardized. The sample information is reported below. At the .10 significance level, can we conclude that there is a difference in the amounts quoted? Two-Sample Tests of Hypothesis 401 Progressive GEICO Family Car Insurance Mutual Insurance Becker \$2,090 \$1,610 Berry 1,683 1,247 Cobb 1,402 2,327 Debuck 1,830 1,367 DuBrul 930 1,461 Eckroate 697 1,789 German 1,741 1,621 Glasson 1,129 1,914 King 1,018 1,956 Kucic 1,881 1,772 Meredith 1,571 1,375 Obeid 874 1,527 Price 1,579 1,767 Phillips 1,577 1,636 Tresize 860 1,188

The president of the American Insurance Institute wants to compare the yearly costs of auto insurance offered by two leading companies. He selects a sample of 15 families, some with only a single insured driver, others with several teenage drivers, and pays each family a stipend to contact the two companies and ask for a price q

### Grand Strand Family Medical Center is specifically set up to treat minor medical emergencies for visitors to the Myrtle Beach area. There are two facilities, one in the Little River Area and the other in Murrells Inlet. The Quality Assurance Department wishes to compare the mean waiting time for patients at the two locations. Samples of the waiting times, reported in minutes, follow: Location Waiting Time Little River 31.73 28.77 29.53 22.08 29.47 18.60 32.94 25.18 29.82 26.49 Murrells Inlet 22.93 23.92 26.92 27.20 26.44 25.62 30.61 29.44 23.09 23.10 26.69 22.31 Assume the population standard deviations are not the same. At the .05 significance level, is there a difference in the mean waiting time? Please show step-by-step solution.

Grand Strand Family Medical Center is specifically set up to treat minor medical emergencies for visitors to the Myrtle Beach area. There are two facilities, one in the Little River Area and the other in Murrells Inlet. The Quality Assurance Department wishes to compare the mean waiting time for patients at the two locations. Sa

### Statistics and probability of the crew on the Titanic

The table below summarizes the fate of the passengers and crew. A common rule of the sea is that when a ship is threatened with sinking, women and children are the first to be saved. Fate of passengers and crew on the Titanic: ____________________________________________________________ Men

### Mean Driving Distance

Callaway Golf is one of the leading golf equipment manufacturers in the United States. The company's R&D department has created three new golf ball designs (GB1, GB2 and GB3) that result in reduced air drag and thereby increase driving distance. The company currently has three distinct brands of driver clubs: FX1, FX2 and FX3.

### Golf Cental: Do golf club brands differ in mean distance

See data file attached. You are the research director at the golf magazine 'Golf Central'. Your magazine decides to test three different brands of 3-iron golf clubs and rate the three brands with regards to the distance. You randomly recruit 5 golfers to test each of the three brands of 3-iron clubs. Each golfer uses all thr

### Data analysis for a financial services company: Mean revenue under marketed plan

The financial data file is attached but you need spss to open the file. Data analysis for a financial services company. There are three different Investment Plans that the company could offer to its customers . You are asked to find out if the expected revenue from marketing any one of these plans is different from the other

### Statistics: Test for proportion of citizens who favor increasing the cigarette tax

A recent study conducted by the state government attempts to determine whether the voting public supports further increase in cigarette taxes. The opinion poll recently sampled 1500 voting age citizens. 1020 of the sampled citizens were in favor of an increase in cigarette taxes. The state government would like to decide if

### Statistics: Random sample of adults from USA and Germany who support death penalty

In an opinion survey, a random sample of 1000 adults from the U.S.A and 1000 adults from Germany were asked whether they supported the death penalty. 590 American adults and 560 German adults indicated that they supported the death penalty. The researcher wants to know if there is sufficient evidence to conclude that the pro

### Statistics: Multiple regression model; difference between two means

Please choose the correct answers and write briefly why: For a given multiple regression model with three independent variables, the value of the adjusted multiple coefficient of determination is _________ less than R2. a. Always b. Sometimes c. Never d. Can be greater or less depending on the standard error

### test Statistic from Hypothesis testing

Please determine the correct answer and write briefly why: A manufacturing operation consists of a unique system that produces an average of 15.5 jet engine propulsion parts every hour. After undergoing a complete overhaul, the system was monitored by observing the number of parts produced in each of sixteen randomly selected

### Evaluate hypothesis statements: Are they sufficient?

Evaluate and discuss the following hypothesis based on what you have learned about hypothesis statements. Should they be written differently, or are the sufficient the way they are stated? a- Investigating the use of video feedback in changing specific teacher behavior. b- The effect of modified teacher behavior on

### Hypothesis Testing of Proportions..

See attached file for proper format. Please solve the exercise below in Excel and show your work (and formulas) 1. At &#945; =..05 and .10, test the hypothesis that the proportion of Consumer (CON) industry companies winter quarter profit growth is more than 2% greater than the proportion of Banking (BKG) companies winter

### Hypothesis test comparing means: Does one town dine out more than another town?

Restaurateur Danny Valentine is evaluating two, sites, Raymondville and Rosenber, for his next restaurant. Denny suspects that Raymondville residents (population 1) dine out more often (number of times per month) than Rosenberg residents (population 2). Denny commissions a market survey to test his hypothesis. The market