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Hypothesis Testing

Database analysis

I need to know which statistical test to use. I want to compare type of malaria contracted (4 categories) vs gender (M or F)so see if there is a) If there are more males than females catching ech of the four different malaria types and b)if there is a higher number of males and a higher number of females catching a particla

Hypothesis that women smile more

Louise was conducting a study to test her hypothesis that women smile more often than her male participants. Her hypothesis will probably be confirmed due to a. Social desirability b. Reactivity c. Experimentor expectancies d. Habituation I think that the answer is c. Am I on the right track?

Find the critical value of the test and apply decision rule

As a part of a class project, your statistics instructor asks you to weigh a sample of 100 items from a shipment of 500. You are testing the null hypothesis that the mean is greater or equal to 10 lbs. You are given that the standard diviation is 0.05 lb. Accepting H0 is the same as accepting the shipment. A) using a signific

Studying effects on small rewards on intrinsic motivation is listed.

Patrick was studying effects of small rewards (such as candy, gum, and soda pop) on intrinsic motivation. He tested fifth-grade children in a special room set aside by the school. Although he asked participants not to tell the students about the study, several children talked to their friends on the playground. Now some of hi

Significance Level

10.42 Nitrogen and Seagrass. The seagrass Thalassia testudinum is an integral part of the Texas coastal ecosystem. Essential to the growth of T. testudinum is ammonium. Researchers Kun-Seop Lee and Kenneth H. Dunton of the Marine Science Institute of the University of Texas at Austin noticed that the seagrass beds in Corpus C

Test of independence

This is a generic question: A researcher who uses a "test of independence" to analyze his data in using a(n) a. Two way chi-squared test b. Independent-samples-test c. Dependent-samples t-test d. Meta-analysis

Ten true-false questions about the sample mean and sample variance calculated on a sample from a normal distribution and using the mean and standard deviaton when testing hypotheses.

Please use words to describe the solution process. In the statements that follow, X is a normally distributed random variable with mean [symbol1] and variance [symbol2]. Furthermore, X1,...,Xn are independent random variables wit the same distribution as X ... Please see attachment for complete question and proper citation

Independent & Dependent variables

Choose a hypothesis and operationally define a variable in the hypothesis. Your operational definition will consist of measures at the self-report, behavioral, and physiological levels as well as a manipulation of the variable. Your operational definition should be written in such a way that you could measure and manipulate it


10.48 Nitrogen and Seagrass. Refer to Exercise 10.42. a. Determine a 98% confidence interval for the difference, M1-M2, between the mean sediment ammonium concentrations in CCB and LLM.

Inferences from Two Samples

A) State the null and alternate hypothesis. B) Determine the rejection region. For example "if , then reject ". C) Determine the Test Statistic. D) Conclude either "Reject " or "Do not reject " based on your analysis and answer the question. E) Determine the p value of the test. Note: Please show how everything was

Sample z test

Directions: Perform a one sample z test for a population mean using the p value approach. Be sure to state the hypothese and the significance leve, to compute the value of the test statistics, to obtain the p value and to state your conclusion. Question: In 1990, the average duration of long distance telephone calls originati

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


Teachers will not use a book in Grade 5 unless the reading level for a typical page can be shown to be above grade level 4.000. Grade level measurements are summarized: n=10, x bar=5.108, s=1.412 Use a 0.05 significance level to test claim that the mean is greater than 4.000. Assume simple random sample and that the pop of means

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


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 signifigant diff using a o

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

From Bill's writing, we know that his average sentence length was 10.4 A paper has 59 sentences with an average length of 8.9, with a SD of 2.7. Test whether this paper was written by Bill.

Calculation of Expectation

Z ~ N (0,1), other variables, except those dependent on Z are constants. The problem is to find expectation of C. Please, express expectation in terms of constant and show how you do that. S0=50; K=52 r=0.05 sigma=0.5 T=30

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