Explore BrainMass
Share

Hypothesis Testing

Biostatistics: 6.2 dietary study; 6.4 convulsive disorders

See Attached file. Please solve in detail show all calculations, reasoning, method used and what a 2 sided p value means in this problem (6.2) For 6.4 please explain the solution in steps and the method used and the meaning of the significance levels

BioStatistics: Computing p value using ptilda

Attached find example 6.7 from BioStatistics by Van Belle. Can someone please work out the problem in detail including explanations and calculations of the ptilda values. Please explain what ptilda is and how does one compute the p value using ptilda. Please give a clear complete explanation of the solution in detail

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: Assess the effectiveness of Lovastatin

Does Lovastatin (a cholesterol-lowering drug) reduce the risk of heart attack? 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

Average amount of sleep that you get to the national average

Compare the average amount of sleep that you get to the national average of 6.9, with a standard deviation of 1.38. State a research (non-directional) hypothesis and a null hypothesis about the populations Determine the cutoff sample score at a significance level of 5% Calculate a Zobt score Compare the Zobt to the Zcrit

The 5-Step Hypothesis Test

Describe the 5-Step Hypothesis Test for a particular claim related to your work or life environment. (This should be a test of one-sample mean or one-sample proportion. The test may be based on a large or a small sample. The decision rule may be based on critical values, or on the p-value.) You need to state the claim, defin

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

Hypothesis Testing of Variance: Cereal box filling weight

The filling weight for boxes of cereal is designed to have a variance .02 ounces or less. A sample of 41 boxes of cereal shows a sample standard deviation of .16 ounces. Use alpha = .05 to determine whether the variance in the cereal box filling weight is exceeding the design specification.

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

A statewide real estate sales agency, Farm Associates, specializes in selling farm property in the state of Nebraska. Their records indicate that the mean selling time of farm property is 90 days. Because of recent drought conditions, they believe that the mean selling time is now greater than 90 days.

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

Computing the Z-Value

A normal population has a mean of 50 and a standard deviation of 7. a) Compute the Z- value associated with 45? Ans: -0.71 b) What % of the population is between 45 and 60? Ans: 72.9% c) What percent of the population is less than 55? Ans: 76.11% Provide detailed explanations for answers.

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

Null hypothesis or research hypothesis

Research Design Considerations a. Describe some of the issues or concerns (at least three) which would be addressed in deciding how to perform a statistical test of a hypothesis: b. As an Argosy student, you are designing a training program to help develop team cohesiveness in a healthcare facility. You have a before and a