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Hypothesis Testing customer service department: Average call length at call center

See attached files. Assume all data/output is normal. 4. The manager of the customer service department at was concerned about the performance of their call center employees. He found that average call times were higher than industry average. The manager decides to invest in a program to train his call center emplo

Statistics MLB 1, 2, 3: Mean incomeby district, aspirin tablets, emphysema drugs

MLB 1 A study was conducted to determine if persons in surburan district I have a different mean income from those in district II. A random sample of 50 homeowners was taken in district I. Although 50 homeowners were to be interviewed in district II also, one person refused to provide the information requested. So only 49 ob

Which yogurt should have highest amount of space

Please state the hypothesis (statistically) and explain the type (the name) of test I need to run. Please do not do anything else on this one. 1) An organic food retailer sells three types of natural yogurt: plain, low fat and fat-free. The retailer wishes to expand the shelf space allocated to yogurt and decides to allocate

Hypothesis Testing: Consumption of Saturated Fats

Consumption of Saturated Fat: A nutritionist claims that the proportion of females who consume too much saturated fat is lower than the proportion of males who consume too much saturated fat. In interviews with 513 randomly selected females, she determines that 300 consume too much saturated fat. In interviews with 564 randomly

Analyze sample data for time spent going to parties by college freshman

1. National data show that, on average, college freshman spend 7.5 hours a week going to parties. President DeRosa doesn't believe that these figures apply at his school; he thinks freshman at his school party less. He takes a simple random sample of 50 freshmen and interviews them. He asks you to analyze his sample data. You de

Test hypothesis that automakers will produce midsized cars

Suppose the federal government gives a substantial tax break to automakers producing midsized cars that get a mean mileage exceeding 31 MPG. A sample of 49 mileages has a mean x-bar of 31.350 and a standard deviation of s=0.799. Let u be the midsize car's mean mileage. Assume alpha=0.01 a) The following questions, represen


1.A sample of 64 college students are asked their weekly (at school) expenses during the fall term. The enquire resulted in a mean of $55 with a standard deviation of $12. Construct a 95% confidence interval for the mean expense for all the students in the school. a. Value from the table ____________ b. The confidence i

Compare data between men and women regarding ACT scores and college GPA

How to determine the difference between men and women regarding ACT scores and college GPA Show my findings Describe what they mean ACT Score College GPA Gender 28 1.72 M 25 3.51 M 21 2.45 F 19 2.85 F 22 2.84 M 15 3.46 F 26 1.97 F 20 3.47 F 23 3.47 M 22 4 M 16 2.94 F 21 1.9 F 23 3.25 M 17 3.23 F 25 3.51 M 19

Analyze mileage and vehicle weight vs miles per gallon data

See attached file. Using Data set 'G', 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 required gr

Hypothesis - Null & Alternative, p-value for F-test; 2-Way ANOVA

See attached file. Hypothesis - Null & Alternative, p-value for F-test (ANOVA) - How to determine significance difference in means 1) An investor wants to know if a difference exists, at a significance level of 0.05, between home prices in three subdivisions. Independent samples of homes from each of the three subdivis

Hypothesis Test

The Rocky Mountain district sales manager of Rath Publishing, Inc., a college textbook publishing company, claims that the sales representatives make an average of 36 sales calls per week on professors. Several reps say that this estimate is too low. To investigate, a random sample of 32 sales representatives reveals that the me


1) If the correlation coefficient r is equal to 0.57, find the coefficient of determination. a) 0.68 b) 0.75 c) 0.45 d) 0.32 2) The prediction interval around y' for a specific x is a) A confidence interval for the true mean value of the y values that correspond to that x b) The value of y used to calculate the slo

Hypothesis Testing: Effects of insecticide DDT on wild birds in Sumatra

Assume that an ecologist is studying the effects of the insecticide DDT on wild birds in Sumatra. DDT sprayed on insects and vegetation subsequently eaten by female birds seems to affect the thickness of their eggshells and thus affects the protection of the embryonic birds. Assume the ecologist knows that the mean eggshell th

One Sample Tests of Hypothesis: Prop bets at Mirage for Super Bowl Sunday

According to news reports, Las Vegas betting parlors increased the number of proposition (prop) bets available to gamblers for this year's Super Bowl (Example: Which team will be the first to suspend a starting player for a team rules violation?). It is believed that the mean number of prop bets per typical gambler is normally

Statistics: Poisson Distribution, Nonconforming parts in sample, average service time Produce trucks arrive at the weigh station at the California border at a rate of 3 per hour according to a Poisson distribution. Livestock trucks arrive at that same weigh station at a rate of 2 per hour according to a Poisson distribution. What is the probability that the number of livestock trucks arriving at the weigh station in two hours is less than 3?

Question 1 Produce trucks arrive at the weigh station at the California border at a rate of 3 per hour according to a Poisson distribution. Livestock trucks arrive at that same weigh station at a rate of 2 per hour according to a Poisson distribution. What is the probability that the number of livestock trucks arriving at the

More variation in the processing time of the new machine

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

Hypothesis Testing of Mean:IQ scores of Statistics Professor

Null and Alternative hypothesis. For the following claim, find the null and alternative hypotheses, test statistic, P-value, critical value, and draw a conclusion. Assume that a simple random sample has been selected from a normally distributed population. Answer parts a-e. Claim: The mean IQ score of statistics professors

Hypothesis Testing: Independent Sample t Test..

See the attached file for the data. Insurance adjusters are concerned about the high estimates they are receiving from Jocko's Garage. To see if the estimates are unreasonably high, each of 10 damaged cars was taken to Jocko's and to another garage and the estimates recorded. Here are the results: Test the null hypothesi

Conducting a hypothesis test for a population mean

Please help with the following problem. You have a sample size of 120 and the population standard deviation of 20. You are testing the null hypothesis of whether the population mean is 120 or not. A. What are the critical values for rejection when Type I error is 5%? B. If actual mean is 121, find the Type II error C.

Pew Research Automobiles Driving

8.14 Do you enjoy driving your car? The Pew Research Center recently polled n = 1048 U. S. drivers and found that 69% enjoyed driving their automobiles. (a) Construct a 95% confidence interval for the proportion of U. S. drivers who enjoy driving their automobiles. (b) In 1991, a Gallup Poll reported this percent to be 79%


1. Different neighbourhoods may have different crime statistics. A sample of 10 days in Neighbourhood A revealed the following number of crimes per day: 15 12 16 17 15 14 16 10 12 14 A sample of 12 days in Neighbourhood B revealed the following number of crimes per day: 17 13 15 18 16 19 11 21 22 13 16 18 At a 5% l

Statistics: Does ad placement matter?

Does ad placement matter? Corporate advertising tries to enhance the image of the corporation. A study compared two ads from two sources, the Wall Street Journal and the National Enquirer. Subjects were asked to pretend that their company was considering a major investment in Performax, the fictitious sportswear firm in the ads.

Statistics: Analysis of food intake and weight gain

Food intake and weight gain. If we increase our food intake, we generally gain weight. Nutrition scientists can calculate the amount of weight gain that would be associated with a given increase in calories. In one study, 16 nonobese adults, aged 25 to 36 years, were fed 1000 calories per day in excess of the calories needed to

Statistics: Tessler Electric utility, sample of telephone response time

Tessler Electric utility requires service operators to answer the telephone calls from customers in an average time of 0.1 minute or less. A sample of 30 actual operator times are drawn, and the results are given in the following table. In addition, operators are expected to determine customer needs and either respond to them

Professor Pink Panther's test; Dr. Sehr Kurz's summary data

Quiz #4 Professor Pink Panther is a referee (reviewer) for a prestigious international journal, Manuscripta Absurda. Recently, he is giving two articles to review. The following information is for Questions 1 through 5. There are two personality types, Type-A and Type-B. Married couples are made up of three

Statistical Problems for Standard Deviation Distribution

Problem 2b: For a population that has a standard deviation of 10, figure the standard deviation of the distribution of means for samples of size- (b) 3. Problem 6: For each of the following samples that were given an experimental treatment, test whether these samples represent populations that are different from the general

Null and Alternative Hypothesis for Filling Soft Drink Bottles

A soft drink filling machine , when in perfect adjustment, fills the bottles with 12 oz. of soft drink. Any over filling or under filling results in the shutdown and readjustment of the machine. -To determine whether or not the machine is properly adjusted, the correct hypothesis is: a) Ho: μ < 12 H1: Μ ≤

Forecast: Thiel's U Statistic, ME, MSE, RMSE, MAPE and Forecast Error

See attached Excel data file. For each forecast, set up columns and calculate: Error Squared error Absolute error Absolute % error The numerator of Thiel"s U statistic The denominator of Thiel"s U statistic Calculate ME, MSE, RMSE, MAPE, and U. Questions. 1/ The absolute percentage error for the data point 9/24/