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Hypothesis Testing

General Statistics: Rejection Region, Critical Value Etc.

See the attached file. For each exercise, determine the a. rejection region b. nonrejectoin region c. critical value (s) d. significance level e. Identify the hypothesis test as two tailed, left tailed, or right tailed. 9.16 A graphical display of the decision criterion is: {see attachment} 9.18 A graphical displa

Test of hypothesis, Sample Size

1. Erthromyacine is a drug that has been related with side effects during pregnancy. Assume that 30% of women experience side effects between the 24th and 28th week of pregnancy. Furthermore suppose that of 200 women who are taking the drug 110 complain of nausea. Test the hypothesis that the incidence rate of nausea for the dr

Sample / Standard Deviation

In a study of quantities of rice consumed in two different cities, a sample data looks as in the attachment. Sampling units were families of four, data is for a year. a. Would it be reasonable to conclude (95 percent confidence) that the two cities were statistically different in the average quantities of rice they consumed p

Hypothesis Test for a Population Mean

Monitoring the ecological health of the Everglades-the bottom temperatures are recorded at the Garfield Bight station and the mean of 19.7 degrees C is obtained for 62 temperatures on 62 different days. Assuming sigma=1.6 degrees C, test claim that the pop mean is less than 20.0 degrees C. Use a 0.05 significance level to calcul

Hypothesis Testing; Significance Level

I) State the null and alternate hypothesis. II) Determine the rejection region. For example "if {see attachment}, then reject {see attachment}". III) Determine the Test Statistic. IV) Conclude either "Reject " or "Do not reject " based on your analysis and answer the question (either YES or NO) . V) Determine the p value of

Stats: Detecting a Significant Difference using One-Tailed Test

5 patients have a mean diastolic blood level of 95 are recruited for a study one month long. After one month the observed mean decline in diastolic blood pressure in these five patients is 4.8 with a standard deviation on 9. 7.32 how many patients would be needed to have a 90% chance of detecting a significant diff using a one

Eight hypothesis testing problems

The mean and serum level in 12 patients 24 hours after they recieved a newly proposed anitbiotic was 1.2 7.1 if the mean and standard deviation of the serum are 1 and 0.4 then using a signifigance level of 0.05 test if the mean serum level of this group is diff from the general population. 7.2 what is the p-value for the t

Hypothesis testing (Two population)

A sample of 65 observations is selected from one population. The sample mean is 2.67 and the sample standard deviation is 0.75. A sample of 50 observations is selected from a second population. The sample mean is 2.59 and the sample standard deviation is 0.66. Conduct the following test of hypothesis using the .08 significanc

Inferential Tests

Question: An analyst working at BC Statistics is compiling a report on the use of the internet at home. In 1997, 250 randomly selected people were asked about the average amount of time spent on the internet per week. The same 250 people were re-surveyed in June 2000. Which test should the analyst to determine whether the home u

Kruskall-Wallis Test.

Kruskall-Wallis Test A large corporation has been sending many of its first-level managers to an off-site supervisory skills course. Four different management development centers offer this course, and the corporation wants to determine whether they differ in the quality of training provided. A sample of 20 employees who have

A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The researcher is interested in determining whether there is evidence that the two processes yields different average errors from the industry standard.

A national manufacturer of ball bearings is experimenting with two different processes for producing precision ball bearings. It is important that the diameters be as close as possible to an industry standard. The output from each process is sampled and the average error from the industry standard is calculated. The results are

Hypothesis for a comparison test

State the null and alternate hypotheses, the decision rule, find the test statistic, state my decision, and estimate the P value for the following: An egg farmer wanted to determine if increasing the time the lights were on in his hen house would increase egg production. For a sample of eight chickens he determined

Hypothesis Problem

State the null and alternate hypotheses, the decision rule, find the test statistic, state your decision, and estimate the P value for the following: The mean high temperature for 12 days in July in Detroit, Michigan was 88 degrees with a standard deviation of 4 degrees. The mean high temperature in Hilton Head, S

Hypothesis Analysis

State the null and alternate hypotheses, the decision rule, find the test statistic, state the decision, and estimate the P value for the following: A sample of 200 Lion Store charge customers 50 years or older showed that 20 did not pay their entire balance at the end of the month. A sample of 300 customers under 30 showed

One-Way Anova Problem - Bottle Design

A consumer preference study involving three different bottle designs (A, B, and C) for the jumbo size of a new liquid laundry detergent was carried out using a randomized block experimental design, with supermarkets as blocks. Specifically, four supermarkets were supplied with all three-bottle designs, which were priced the same

Null and alternate hypothesis

Figure out 1). H0 and H1 and 1). the decision rule. The Andersons Super Dollar had two grocery stores in Erie, Pennsylvania. The mean time customers wait in the checkout line at the Byrne Road store is 3.7 minute with a standard deviation of .8 minutes, for a sample of 40 customers. The mean waiting time for the I-


The types of raw material used to construct stone tools found at the archaeological site Casa del rito are shown below (Bandelier Archaelogical Excavation Project, edited by Kohler and Root). A random sample of 1946 stone tools was obtained from a current excavation site. SEE ATTACHMENT Use a 5% level of significant to te

Null and Alternate Hypothesis : key information

6. The manufacturer of a particular all-season tire claims that the tires last for 22,000 miles. After purchasing the tires you discover that yours did not last the full 22,000 miles. Suppose that a sample of 100 tires made by that manufactures lasted on average 21,819 miles with a sample standard deviation of 1,295 miles. I

Associated P-Value

4. Consider the following scenario: Thomas Kaczy, owner of Hamilton Poultry, a national poultry distributor, based in New Hampshire, reported data on high egg production of Rhode Island Red hens. The number of eggs produced were 25, 28, 17, 26, 27, 22, 25, and 30. He was interested in determining if he could conclude that th

Weight Loss Test

Test suggests that the average client loses 15 lbs during the first month feels the actual number of pounds loss is less than this tested the claim by selecting 30 of the clients at random and obtain the following data: Pounsd lost during the 1st Month: 16 20 14 15 14 18 19 20 09 13 20 11 12 18 13 17 11 21


The Human Resources Director of Wayjacks Inc. has administered a dexterity test to job applicants for a period of several years. She assumes that the times required to complete the task are distributed with a mean of 10.8 minutes. The Director would like to know if applicants who have completed a vocational course tend to compl


An auditor for a government agency is assigned to the task of evaluating reimbursement for office visits to doctors paid by Medicare. The audit is to be conducted for all Medicare payments in a particular area during a certain month. An audit is conducted on a sample of 75 of the reimbursements with the following results. Ave

Inference One Pop

The manager of a big travel agency monitors agents who do booking for service by phone. The average time for a phone call, in seconds, is used as one summary of activity for the agency. Phone calls that are in excess of the 18.6 minutes are considered to be inefficient since they tend to tie up phone lines and in the long run


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

Estimating a Population Mean for Large and Small Samples

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

True Population - 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