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Hypothesis Testing


A) Write the estimated regression equation. b) Comput the F statistic and test the significance of the relationship at the 0.05 level of significance... (See attachment for full background and all questions)


Shawn and Kevin, two young men in their mid-twenties, have been close friends since they met during their college years. They share numerous similar interests and greatly enjoy each other's company. Kevin gratefully acknowledges to himself that Shawn has been a fine friend in every respect that counts. Shawn has listened patient

Only for 103139,103997, 103866, 103940, or 103642 only

Only for above OTA's. All others will be called in. Thank you. I am having a lot of trouble understanding statistics even thoughI have studied. In an attempt to pull the pieces together,I am looking for the following to be explained. Please only accept this if you are willing to take the time to explain clearly all, a-f for eac

How many people must they survey

A marketing firm wants to know the proportion of Sox fans in the Chicago area within a margin of error of 8 percentage points How many people must they survey to be 99% confident that the true population proportion for the Chicago area is within this margin of error? (No prior knowledge regarding proportion is available).

hypothesis test for difference in means using a z-statistic

A study was conducted on the annual incomes of corporate trainers in the state of New York, in metropolitan areas of less than 100,000, and in metropolitan areas having a population of over 500,000. Some sample statistics are: Sample Statistic Population less than 100K Population more than 500K Sample Size 45 60 Sample Mean

Test of Hypothesis and about P-Value

Health care reform was one of the major platforms of the Clinton campaign in 1992 and one of the top priorities of his new administration in 1993. One of the polls taken after President Clinton's inauguration indicated that 273 of 521 registered voters believed that health care reform should be the leading priority of the new p


An insurance company is thinking about offering discounts on its life insurance policies to nonsmokers. As part of its analysis it randomly selects 200 men who are 60 years old and asks them whether or not they smoke at least one pack of cigarettes per day and whether they have ever suffered from heart disease. The results are s

Inference in the Yellow Pages Effect

To determine the effect of advertising in the Yellow Pages, Bell Telephone took a sample of 40 retail stores that did not advertise in the Yellow Pages last year but did so this year. The annual sales(in thousands of dollars) for each store in both years were recorded and stored in file yellow pages a. Estimate with 90% confide


One factor in low productivity is the amount of time wasted by workers. Wasted time includes time spent cleaning up mistakes, waiting for more material and equipment, and performing any other activity not related to production. In a project designed to examine the problem, an operations management consultant took a survey of 200

T stats

The American Medical Association conducts surveys of its members each year. A sample of physicians is selected and asked to report the amount of time each devotes to patient care each week. The results for the survey are stored in the excel file. Can we infer that the mean amount of time devoted to patient care per week by all p

restaurant site is acceptable based on pedestrian traffic.

A fast food franchiser is considering building a restaurant at a certain location. Based on financial analyses, a site is acceptable only if the number of pedestrian passing the location averages more than 100 per hour. The number of pedestrians observed for each of 40 hours was recorded and stored in the attached excel file .


In an attempt to reduce the number of person-hours lost as a result of industrial accidents, a large production plant installed new safety equipment. In a test of the effectiveness of the equipment, a random sample of 50 departments was chosen. The number of person-hours lost in the month prior to and the month after the install

Expectation and Hypothesis Testing

4. An experiment is set to test the hypothesis that a given coin is unbiased. The decision rule is the following: Accept the hypothesis if the number of heads in a sample of 200 tosses is between 90 and 110 inclusive, otherwise reject the hypothesis. a) Find the probability of accepting the hypothesis when it is correct.

Statistics problems

Please explain fully, using Excel when necesary. These questions were addressed once already, but they were not explained in a way in which they could be fully understood. Please detail each step. Thanks! 1)A publisher is considering three different covers for a new magazine. A random sample of 90 people are asked to pick the

Statistics problems

Please use Excel when necessary: 1) When the p-value is smaller than the significance level: a) A type 1 error is committed b) A type 11 error is committed c) The null hypothesis is rejected d) The critical value is correct. Problem # 2) The coefficient of correlation between the variables X and Y was computed to be -0.6

That there are no differences between the two groups of subjects

A) Analyse the data below to test the hypotheses that there are no differences between the two groups of subjects in terms of their walking time to exhaustion (in seconds) and ratings of perceived exertion (RPE) after 8 minutes of walking. Healthy subjects --------------------------------------------------------------------

Sample proportion hypotheses test

Ho: P<= .7 Ha: P > .7 Sample Data Set: 300 Sample Proportion of .853 What is the standard error of the proportion? What is the z-test? How do you compute the p value? What do you do with the Ho?

Biopstatistics Problem

I hope you can help me with this problem. I have 2 questions regarding this study. 1) I have heard from my teacher that there is a 7th null hypothesis hidden in the text for this study. The first 6 are presented in the tables. WHAT IS THE 7TH NULL HYPOTHESIS??? They are: Ho1: Cr 3+and As3+ has no effect on glucose to

Using Spearman's - Is my data statistically significant?

Hi there, I used excel to analyze my data with spearmans rank order co efficient test and came up with the attached table. I have a query about finding out whether my correlation coefficient - 0.420- is statistically significant. This is what i understand (not much!) - take the t value and compare it to the critical val

Statistics Problem

Can you tell me how you would do the attached problem? My idea is to take the difference of Day 0 and Day 365 (using the absolute value of it) then use ANOVA. Does that make sense?

What you need to know about null hypothesis?

Here is the scenario: Suppose we hypothesize that there is a negative (inverse) relationship between treatment and depression. We'd like to test this hypothesis, so we obtain two samples. Sample 1 is drawn from a population of depressed persons who have not received any type of treatment. Sample 2 is drawn from a population o

Statistics question

A researcher hypothesizes that the lowering in cholesterol associated with weight loss is really due to exercise. To test this, the researcher carefully controls for exercise while comparing the cholesterol levels of a group of subjects who lose weight dieting with a control group that does not diet. The difference in mean chole

Hypothesis Testing: Average Speed

Question: Suppose a candidate running for sheriff claims that she will reduce the average speed of emergency response to less than 30 minutes. (30 minutes is thought to be the average response time with the current sheriff.) There are no past records, so the actual standard deviation of such response times cannot be determined.