Explore BrainMass

Hypothesis Testing

Hypothesis Testing of Mean: Number of Patients per Day

The post anesthesia care area (recovery room) at St. Luke's Hospital in Maumee, Ohio 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 revealed the following numbers of patients. 25 27 25 26 25 28 28 27 24 26

10.74 IRS audits: P-Value - 0.10 Level of Significance

It has been reported that 80% of taxpayers who are audited by the Internal Reve- nue Service end up paying more money in taxes. Assume that auditors are random- ly assigned to cases, and that one of the ways the IRS oversees its auditors is to monitor the percentage of cases that result in the taxpa

10.57 Insurance Information Institute: P-Value - Automobile Insurance

SEE ATTACHED FILE - p-Value - Automobile Insurance (10.57) According to the Insurance Information Institute, the mean annual expenditure for automobile insurance for U. S. motorists is $706. Suppose that a government official in North Carolina has surveyed a saimple random sample of 80 residents of

Hypothesis Testing of Mean: Daily coffee consumption

The International Coffee Association has reported the mean daily coffee consumption for U.S. residents as 1.65 cups. Assume that a sample of 38 people from a North Carolina city consumed a mean of 1.84 cups of coffee per day, with a standard deviation of 0.85 cups. In a two-tail test at the 0.05 level, could the residents of thi

Remodeling Magazine: P-Value Population, Standard Deviation

SEE ATTACHED FILE - p-Value Population Standard Deviation (10.33) According to Remodeling magazine, the average cost to convert an existing room into a home office with custom cabinery and rewiring for electronic equipment is $5976. Assuming a population standard deviation of $1000 and the sample of home office conversion

P-Value Approach to Hypothesis Testing

SEE ATTACHED FILE - p-Value Approach to Hypothesis Testing (10.28) For a sample of 12 items from a normally distributed population for which the standard deviation is σ = 17.0, the sample mean is 230.8. At the 0.05 level of significance, test Ho: µ ≤ 220 versus H1:µ > 220. Determine and interpret the p-value f

Problems with Null and Alternative Hypotheses

Many law enforcement agencies use voice-stress analysis to help determine whether persons under interrogation are lying. If the sound frequency of a person's voice changes when asked a question, the presumption is that the person is being untruthful. For this situation, state the null and alternative hypotheses in verbal terms,

Statistics: Calculate p value and interpret; 95% confidence interval; mean, range

PROBLEM 1 NBC TV news, in a segment on the price of gasoline, reported last evening that the mean price nationwide is $1.50 per gallon for self-serve regular unleaded. A random sample of 35 stations in the Milwaukee, WI, area revealed that the mean price was $1.52 per gallon and that the standard deviation was $0.05 per gall

Econometrics Problem

Table 3-6 gives data on X (net profits after tax in U.S. manufacturing industries [$, in millions]) and Y (cash dividend paid quarterly in manufacturing industries [$, in millions]) for years 1974 to 1986. a. What relationship, if any, do you expect between cash dividend and after-tax profits? b. Plot the scattergram between

Statistics: One or two-tailed test, paired sample, ANOVA

See attached file. 25. The management of Discount Furniture, a chain of discount furniture stores in the Northeast, designed an incentive plan for salespeople. To evaluate this innovative plan, 12 salespeople were selected at random, and their weekly incomes before and after the plan were recorde

Business Statistics: Evaluate a new textbook with student sample

Whenever we perform a statistical test, we calculate a so-called p-value, which ranges between 0.00 and 1.00. In general terms, the value of p tells us the probability of drawing a sample WITH THESE CHARACTERISTICS if the null hypothesis is TRUE. Here's a simple example. H1: On average, ten-year-old boys are taller than ten

Statistics: Personality test, lightbulbs, education, insomnia, summer clothing

See attached file for 5 problems. One personality test available on the World Wide Web has a subsection designed to assess the "honesty" of the test-taker. After taking the test and seeing your score for this subsection, you're interested in the mean score, , among the general population on this subsection. The website reports

Hypothesis Test for Mean, Standard Deviation and Type 2 Error

Statistics Hypothesis test for mean time, standard deviation, type II error Executives of a supermarket chain are interested in the amount of time that customers spend in the stores during shopping trips. The mean shopping time, μ spent by customers at the supermarkets has been reported to be 35 minutes, but executives hire a

Descriptive statistics and Hypothesis test for proportion vs. hypothesized value

See attached file for 3 problems: Tesla Motors, PC manufacturer and large insurance company claims 4. Tesla Motors needs to buy axles for their new car. They are considering using Chris Cross Manufacturing as a vendor. Tesla's requirement is that 95% of the axles are 100 cm ± 2 cm. The following data is MegaStat output from

Calculate the mean rating of caseworker for males and females.

1. You are conducting an evaluation of services at a social service agency. One of the evaluation issues is finding out whether male clients rate the quality of casework services as highly as do female clients. You have collected following data on the clients: Gender Rating of Caseworker male 4 female 4 female 5 female 5

Three relevant variables and describe one operationalization

A datum (singular of data) may be either a variable or a constant, depending upon the situation. A variable is something that...well, varies, while is constant is just that. Example: In the general population, sex is a variable. In a monastery, it's a constant. Another example: In the general population, monthly pay is a variabl

Hpothesis Testing and P-Values: Baseball salaries, wins, attendence, AL, NL

Refer to the Baseball Data, which reports information on the 30 Major League Baseball teams. In each instance provide the p-value from your work. Complete the following: a. At the .05 significance level, can we conclude that there is a difference in the mean salary of teams in the American League versus teams in the Natio

Hypothesis Testing: Students at West Virginia sleep less

Each response must include your calculations. This problem requires you to complete all steps for the hypothesis testing process. According to a recent survey, Americans get a mean of 7 hours of sleep per night. A random sample of 50 students at West Virginia University revealed the mean number of hou

Clinical Trial Investigations Effectiveness

3. A clinical trial is run to investigate the effectiveness of an experimental drug in reducing preterm delivery to a drug considered standard care and to placebo. Pregnant women are enrolled and randomly assigned to receive either the experimental drug, the standard drug or placebo. Women are followed through delivery and

Fund managers believes core inflation rate would be higher

In June 2001, 38% of fund managers surveyed believed that the core inflation rate would be higher in 1 year. One month later a similar survey revealed that 22% of fund managers epected the core inflation rate to be higher in one year. Assume that the sample size was 200 in both the June and July surveys. a. Develop a point

Differences between Statistical and Practical Significance

Hypothesis testing determines if results are statistically significant. However, marketing managers want to know if research results are practically significant. What is the difference between these two concepts? How does a researcher explain the difference to a manager? Can the size of a sample affect the difference between sta

Statistics Practice problems: P3, P4, P5, P6

P3. People spend huge sums of money (currently around $5 billion annually) for the purchase of magnets used to treat a wide variety of pains. Researchers conducted a study to determine whether magnets are effective in treating back pain. Pain was measured using the visual analog scale, and the results given below are among the

Write a paper assessing technology's future effect on the workplace.

Please provide me with a simplistic approach, outline or structure for the following assignment. I will write the paper. Assignment: Write a paper assessing technology's future effect on the workplace. * Select an industry with which you are familiar. * Predict how future technology will inform, support, and poten

Statistics: Seat belted drivers, taste of PTC, spam in email

1) The proportion of drivers who use seat belts depends on things like age, gender, ethnicity, and local law. As part of a broader study, investigators observed a random sample off 117 female Hispanic drivers in Boston; 68 of these drivers were wearing seatbelts. Give a 95% interval for the proportion of all female Hispanic driv

Statistics week 10: 10 true false, multiple choice questions

1. Estimation with the independent-measures t statistic is used to determine how much difference there is between two treatment means or two population means. True False 2. If you are using the data from a repeated-measures study to estimate the mean difference between two treatments, the width of the confi