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Hypothesis Testing

Hypothesis testing : Proportion

It has been reported that 80% of taxpayers who are audited by the IRS end up paying more money in taxes. Assume that the auditors are randomly assigned cases and that one of the ways the IRS oversees its auditors is to monitor the percentage of cases that result in the tax payer paying more in taxes. A sample of 400 cases handl

Statistical IQ Testing of Employees

Please explain the answers. Descriptions are in the file. 3. In order to test whether the mean IQ of employees in an organization is greater than 100, a sample of 35 employees is taken and the sample value of the computed test statistic, t_ = 3:5 The null and alternative hypotheses are: A) H0: X = 100; Ha: X 6= 100. B) H0:

Test Findings: sample of difference in wages based on gender

The wages data set has a sample size of 100 people that were surveyed. Our error margin was .05. For the 47 females surveyed the mean wage was $24,451 per year with a standard deviation of $12,455 per year. For the 53 males surveyed the mean wage was $36,492 per year with a standard deviation of $18,447 per year. Check the clai

Statistics - Hypothesis Testing Adjustment

Discuss the link between the estimate and the parameter in the context of an hypothesis test. Be sure to reference the appropriate steps of the five step process in your response, based on the steps below: Step 1: State null and alternate hypothesis. Step 2: Select a level of significance Step 3: Identify the test statisti

Testing of hypothesis problems

Dear OTA, Can you please help me with this homework assignment? Thanks 1. Burney Watt, chief electrician for the Prescott Electrical Coop has been watching the electric bills for 10 properties in Prescottvilla, the up and coming snobby subdivision south of town. The residents there have been complaining that their "b

1. The General Social Survey is an annual survey given to about 1,500 U.S. adults selected at random. 2. The university data center has two main computers. The center wants to examine whether computer 1 is receiving ... [See the attached questions file.]

1. The General Social Survey is an annual survey given to about 1,500 U.S. adults selected at random. Each year, the survey contains several questions meant to probe respondents' views of employment. A recent survey contained the question "How important to your life is having a fulfilling job?" Of the 261 college graduates surve

Regression Analysis of Wine Consumption

Please see the attached file. **All work shown (step by step), in simple terms please!!! No excel, just formulas**. 20) A marketing research firm wished to study the relationship between wine consumption and whether a person likes to watch professional tennis on television. One hundred randomly selected people are as

Significance level and p-value

A large department store hired a researcher to compare the average purchase amounts for the downtown store with that of its mall store.  The information shown was obtained.  At the 0.01 significance level can it be concluded that the mean amount spent at the mall store is larger?Estimate the p-value? Average purchase amount 

Chi-Statistic in Hypothesis Testing

A machine used for packaging seedless golden raisins is set so that their standard deviation in the weight of raisins packaged per box is 0.25 ounce. The operations manager wishes to test the machine setting and selects a sample of 30 consecutive raisin packages filled during the production process. Their weights are as record

Statistics in business

See attachment for problem A student team examined parked cars in four different suburban shopping malls. One hundred vehicles were examined in each location. Research question: A

Do average calls per week differ from district to district?

1. Using the data file TRX.XLS (attached), construct a 95% confidence interval for the average number of prescriptions written for Prilosec. Assume the distribution in normally distributed. There are 24 months to be averaged. Use Descriptive Statistics in Excel and be sure to check the appropriate options. If you can't see the o

Hypothesis Testing

A lumber company has claimed that the standard deviation for the lengths of their 6 foot boards is 0.5 inches or less. To test their claim , a random sample of 17 six-foot boards is selected; and it is determined that the standard deviation of the sample is 0.42. Do the results of the sample support the company's claim? Use alph

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

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

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

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

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

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

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

Non directional hypothesis - Get Super Slim X

Suppose the company that has produced "Get Slim X" now produces an even better diet pill. This new and improved version is called "Get Super Slim X." Health researchers say that the mean weight loss after taking this pill for six months should be 7 pounds. A random sample of 49 people, who want desperately to lose weight, tak

Goodness of Fit Test - Percentage of Payment Methods

The American Bankers Association collects data on the use of credit cards, debit cards, personal checks, and cash when consumers pay for in-store purchases (The Wall Street Journal, December 16, 2003). In 1999, the following usages were reported. In Store Purchase Percentage Credit Card= 22% Debit Card=

Candy Color Percentages for M&M

M&M/MARS, makers of M&M Chocolate Candies, conducted a national poll in which more than 10 million people indicated their preference for a new color. The tally of this poll resulted in the replacement of tan-colored M&Ms with a new blue color. IN the brochure "Colors," made available by M&M/MARS Consumer Affairs, the distribut

Inferences about Two Population Variances on Earnings

The standard deviation in the 12-month earnings per share for 10 companies in the airline industry was 4.27 and the standard deviation in the 12-month earnings per share for 7 companies in the automotive industry was 2.27 (Business Week, August 14, 2000). Conduct a test for the equal variances at a=.05. What is your conclusion

Hypothesis Testing Grocery Bills in Different Towns

A study is performed in a large southern town to determine whether the average weekly grocery bill per four person family in the town is significantly different from the national average. A random sample of the weekly grocery bills of four person families in this town is given in the attached file. a. Assume that the national

Statistics - Hypothesis Testing for IQ Scores

Numerous studies have shown that IQ scores have been increasing, generation by generation, for years (Flynn, 1984, 1999). The increase is called the Flynn Effect, and the data indicate that the increase appears to be about 7 points per decade. To demonstrate this phenomenon, a researcher obtains an IQ test that was written in