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Hypothesis Testing

Stats and Statistics: confidence intervals, p-values, hypothesis testing.

1. After a sample of numbers is taken from a population, the 95% confidence interval is calculated out at {10.5, 12.0} What is the correct way to interpret this confidence interval? Choose one. (1 point) A) 95% of all values in the population are between 10.5 and 12.0 B) The true population mean has to be between 10.5 and

Hypothesis Testing: Compute P-Value

You want to prove that a population mean is not 7. Data is ratio and a large sample size will be used (n = 225). When the sample is done the sample mean is computed to be 7.2 and the sample standard deviation is 1.5. Test the hypothesis using an alpha of 5%. Use formal hypothesis testing and compute the p-value.

SPSS - Parametric testing, Bonferroni multiple comparison

I need help interpreting the attached SPSS output. Consider the variable for respondents' average income (r inc dol) Is the average income for all respondents 31,126.50? Is the average income for people with less than a high school degree 17,366.97? Is the average income for people with graduate degrees 58,128.38? The

Identify a hypothesis from an article

Start by identifying and summarizing the hypothesis described in the article. Then explain whether the hypothesis was rejected or accepted, and what the implications of this finding are for the study. -----------------------------------------------------------------------------------------------------------------------------

Hypothesis Testing: Age of College Juniors

Develop a problem statement. Let's assume that the question deals with the age of college juniors. 1) Establish the null hypothesis (H0) and the alternate hypothesis (H1). 2) Select the level of significance, that is. 3) Select an appropriate test statistic. 4) Formulate a decision rule based on steps 1, 2,

Carver Memorial Hospital

Carver Memorial Hospital's surgeons have a new procedure that they think will decrease the time to perform an appendectomy. A sample of 8 appendectomies using the old method had a mean of 38 minutes with a variance of 36 minutes, while a sample of 10 appendectomies using the experimental method had a mean of 29 minutes with a va

Hypothesis testing proportions

The Web-based company Henrietta Balloons has a goal of processing 96% of its orders on the same day they are received. If 95 out of the next 100 orders were processed on the same day, would this prove that they are exceeding their goal, using a 90% confidence level? A. Choose the Hypothesis B. Specify the Decision R

Hypothesis testing problems using Z and t test

The Board of Surgeons recommends a postoperative examination six months after a prostatectomy. In a sample from the records of Carver Memorial Hospital, follow-up exams were given in 80 out of 200 cases. In a sample of records from HiRent Hospital, follow-up exams were given in 120 out of 200 cases. Normality may be assumed bec

Applied Statistics in Business and Economics - Regression

Prepare answers to the following assignments from the e-text, Applied Statistics in Business and Economics, by Doane and Seward: 12.48 In the following regression, X = weekly pay, Y = income tax withheld, and n = 35 McDonald's employees. (a) Write the fitted regression equation. (b) State the degrees of freedom for a two-tai

Levels of Significance, Hypothesis and Decision Rule

An auditor reviewed 25 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was $275.66 with a standard deviation of $78.11. (a) At the 5 percent level of significance, does this sample prove a violation of the guideline that the a

Important information about Z test for mean

Please provide an explanation and step by step process on how these answers are chosen. In an article appearing in Today's Health a writer states that the average number of calories in a serving of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selec

Managerial Hypotheses Testabilities

Hypothesis testing has been described by some as the use of statistics to determine the probability that a given hypothesis is true. Is this the case. Are real world managerial hypotheses testable? Do you think you could translate real world managerial problems into a testable framework allowing for the application of the metho

Hypothesis Testing: Widgets Produced Per Shift

Please help with the following problem regarding hypothesis testing. Provide a step by step solution. In a given manufacturing environment there are three shifts which produce X thousands of widgets per eight hour shift. Management is concerned that midnight shift is not keeping up with the other shifts, but the numbers for

A one sample test -topic 401K

Identify a research issue, problem, or opportunity that uses either interval or ratio level data (Recall that ratio level data are those data which have an absolute zero. This includes all forms of money, weight, time, or distance.) Some examples of ratio level data include a team member's 401K fund, a team member's stock portfo

Advantages of Accurate Interpretation of Statistics

The types kinds of statistical information collected in your professional setting. Provide examples to illustrate the information/data. b. The advantages of accurate interpretation of statistical information c. How this information is used to improve decision making in your organization

Blockbuster is testing a new policy of waiving all late fees on DVD rentals using a sample of 10 randomly chosen customers. (a) At alpha (a) = .10, does the data show that the mean number of monthly rentals has increased? (b) Is the decision close ? (c) Are you convinced?

Blockbuster is testing a new policy of waiving all late fees on DVD rentals using a sample of 10 randomly chosen customers. (a) At alpha= .10, does the data show that the mean number of monthly rentals has increased? (b) Is the decision close ? (c) Are you convinced? DVDRental Customer No Late fee Late

Two-Tailed Test and P-Value

The top food snacks consumed by adults aged 18-54 are gum, chocolate candy, fresh fruit, potato chips, breath mints/candy, Ice cream, nuts, cookies, bars, yogurt, and crackers. Out of a random sample of 25 men, 15 ranked fresh fruit in their top five snack choices. Out of a random sample of 32 women, 22 ranked fresh fruit in the

Population of Interest

Populations of Interest Many believe that GM's demise could lead to a ripple effect and cause many other businesses to go under. This ripple effect, many think, could cause the United States to slip out of a recession and lead the country into a depression. The group will research this effect to see what populations could be


A sample of size 25 provides a sample variance of 400. The standard error, in this case equal to 4, is best described as the estimate of the standard deviation of means calculated from samples of size 25. Blossom's Flowers purchases roses for sale for Valentine's Day. The roses are purchased for $10 a dozen and are sold for

Degrees of Freedom

A political scientist obtained recordings of election-night acceptance speeches of seven newly elected representatives to the US Congress. She counted the number of minutes devoted to urban problems in these speeches. Four of the representatives were from rural districts and three were from urban districts. Listed below are the

How do you integrate ethics in your professional decision making process?

What is ethics? Ethics is basically concerned with the Moral obligations, responsibilities and social justice of the world. It invokes the idea of "how people should act". What is morals? Morals is your ability to know the difference between good and bad. Ethics is a construct made up of values. Ethical values include love, hone

Statistics Random Samples Z-Test

For the following independent random samples, use the z-test and the 0.01 level of significance in testing Ho:u1 = u2 versus H1:u1 = u2. x1 = 33.5 s1 = 6.4 n1 = 31 x2 = 27.6 s2 = 2.7 n2 = 30 2. The manager's assistant, who created a new brochure, randomly selects 400 current customers, then randoml

Statistics: P-value, Standard Deviation

Please show work! 1. A bottling company needs to produce bottles that will hold 8 ounces of liquid for a local brewery. Periodically, the company gets complaints that their bottles are not holding enough liquid. To test this claim, the bottling company randomly samples 64 bottles and finds the average amount of liquid held by t

Hypothesis Testing: Types of Samples

PROBLEM: Target wants to maintain adequate supplies of various brands of mouthwash to meet the on-going demands of its customers. Target wants to estimate the proportion of its customers who favor the country's leading brand of mouthwash, Scope. Are the data convincing evidence that something other than the historical 13% pre

Perform and independent samples t testt

You are interested in a new method of advertising. In order to test the new procedure they have tested it in eleven markets with the following sales in thousands of dollars: $124; $157; $98; $190; $103; $135; $149; $176; $200; $180; and $256. You also used eleven control markets, which had the following sales in thousands of d

Hypothesis test.

Research has demonstrated that involvement in religious activities seems to benefit health and well-being. Reyes-Ortiz, Ayele, Mulligan, Espino, Berges, and Markides (2006) found that church attendance was significantly related to fear of falling in a sample of Mexican-American aged 70 and over. The following frequency distri

Hypothesis Testing: Confidence Intervals

7. In a packing plant a machine packs cartons with jars. Supposedly a new machine will pack faster on the average than the machine currently used. To test that hypothesis the time it takes each machine to pack 10 cartons are recorded. The results in seconds are shown in the following table. New: 42,41,41.3,41.8,42.4,42.8,43.2,

Z test for population proportion

5. Of the 38 numbers on a roulette wheel, 18 are red, 18 are black and 2 are green. If the wheel is balanced, the probability of the wheel landing on red is 0.474. A gambler has been studying a roulette wheel. If the wheel is out of balance then he can improve his odds of winning. The gambler observed 200 spins of the wheel and