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Hypothesis Testing

Mean, standard deviation and variance

We have two different samples - consisting of bags of M&M's. The first sample consists of 5 bags of M&M's with the following number of blue pieces in each bag 10, 11, 9,10,10. Calculate: A. The mean B. The standard deviation C. The variance The second sample consists of 10 bags with an average number of blue

Statistic Scenarios

Gun Violence. The Harris Poll asked a sample of 1009 adults which causes of death they thought would become more common in the future. Gun violence topped the list; 706 members of the sample thought deaths from guns would increase. Although the samples in national polls are not SRSs, they are similar enough that our method gi

Students t test for the significance of Correlation Coefficient.

The heights and shoe sizes of the starting lineup of a tournament baseball team are listed below. Use a calculator to determine the correlation coefficient. Using a significance level of α=0.05, determine if there is a significant linear correlation between the heights and shoe sizes of the baseball team. Height

Statistic Problem

A statistically significant result occurs when the value of the test statistic falls in the rejection region. A result has practical significance when it is statistically significant and the result also is different enough from results expected under the null hypothesis to be important to the consumer of the results. By taking

Hypothesis Identification Article Analysis

Please use the attached PDF article to help me solve the following problem: Prepare an analysis of your selected article. Start by identifying the hypothesis described in the article, and explain how the hypothesis statement was used in the study. Be sure to properly cite your article, and be prepared to discuss your analysis

Hypothesis Testing and Significance Level

1. If you were to conduct right-tailed hypothesis test at 5% significance level, you choose the critical value this way. Assuming that the null hypothesis is true, you will find the value of the test statistic for which the probability of obtaining a value less than the specified value is 0.05. Is this true? Explain answer.

Probability/statistics/z table/student's t

1. 20 problems 2. If confidence level is not given, assume 95% 3. Please show calculation using formula and using appropriate z table, student's t table, or Poisson table, etc. See attached file for full problem description.

Parametric or Nonparametric Data questions

Please help me with the following: 1. The average life span of a dog is proportational to the amount of calcium consumed. P- Parametric data or NP - nonparametric data? 2. A study of vehicle accidents on a military installation compared to driver's rank. P- Parametric data or NP - nonparametric data?

Hypothesis testing problems

1. The graph portrays the decision criterion for a hypothesis. Determine the significance level. 2. Assume that the data has a normal distribution and the number of observations is greater than fifty. Find the critical z value used to test a null hypothesis if: = 0.05 and the test is right-tailed. 3. Use

Goodness-of-fit Test : Hypothesis Testing

Goodness of fit test : A student was given a die but he had no idea whether or not it was a fair die. He threw the die 480 times and each outcome was recorded. The results are given in the following table. xi 1 2 3 4 5 6 Oi 80 105 95 64 79 57 Test, at the 5% level of significance, whether or not this die is fair. You must s

Hypothesis Analysis traditional and P value method

Problem #6 Investor's Business Daily The mean length of a work week for the population of workers was reported to be 39.2 hours (Investor's Business Daily, September 11, 2000). Suppose that we would like to take a current sample of workers to see whether the mean length of a work week has changed from the previously reported 39

Hypothesis Test

You want to check the claim that the Laurelhurst area has higher day care charges then the non Laurelhurst areas. Test the hypothesis that the Laurelhurst area has a higher daycare charge per month from the date below. LAURELHURST NON-LAURELHURST 500

Hypothesis Test - Frozen Dinner

Your company manufactures low calorie frozen dinners. The advertised calorie content is 200 calories. A consumer activist group, FACT: fat and calories tribunal, is claiming that your product is not consistent. In fact, they contain more than 200 calories. Run a hypothesis test proving that your dinners are less then 200 calorie

Goodness of Fitness

You own a small tea company, Sweet Leaf, NASDQ ticker symbol LEAF. You are looking at marketing costs versus benefits. Your production manager says it doesn't matter which tea you produce, all tea is the same. You say otherwise. You hire a consumer research firm headed my Matt Stat. He randomly interviews 100 consumers of your t

Random Sample - Test Scores

In the past, 38% of all students pass the state high school exam on their first try. A school posts a first time passing rate of 56%. If the school had a sample size of 324, is the school's 56% really any different that the state's 38%?

Hypothesis Test

The scores of 133 males and 162 females on a test that measures a person's feelings are shown in the table below. Your conjecture is the "the feelings" of males and females in the population are different. Run a hypothesis test to check this proposition. Group Sample size x-bar Standard Deviation of the samp

proportion testing for SAT scores

Two high school principals are arguing about who has the better school. This principal for Hard Rock High, Desi Mall, draws a random sample of 100 of her seniors and finds that 75% scored above 650 on the math portion of the SAT. Sharon N. Formation, the principal of Preppy Magnet School, drew a sample of 25 students and found t

Description of Statistics - Hypothesis Test

North Carolina State University looked at the factors that affect the success of students in a required chemical engineering course. Students must get a C or better in the course in order to continue as chemical engineering majors. There were 65 students from urban or suburban backgrounds, and 52 of these students succeeded. Ano

Breathing Pattern Statistics

#4 In a study of hypnosis, breathing patterns were observed in an experimental group of subjects in a control group. The measurements of total ventilation (liters of air per minute per square meter of body area) are shown below. We want to know whether the groups follow the same distribution. Unfortunately, we cannot assume

Statistics on Heart Disease

#3 Heart disease patients often experience spasms of the coronary arteries. Because biological amines such as serotonin may play a role in these spasms, a research team measured serotonin levels post-mortem from patients who died of heart disease and from a control group that died of other causes. The data are summarized in t

Predict the number of ovarioles from the pupal size

Webber studied the relationship between pupal weight (in milligrams) and the number of ovarioles in females of the blowfly. We want to predict the number of ovarioles from the pupal size. (see table "Pupae" in Excel) 9.1 What test or procedure should be performed? 9.2 Perform the test and assess its significance. 9.3

State Null and Alternate Hypothesis

1. A sample of 64 observations is selected from a normal population. The sample mean is 216, and the sample standard deviation is 15. Conduct the following test of hypothesis sing the .03 significance level. H0: µ ≥220 H1: µ < 220 a. State the null and the alternate hypothesis b. State the decision rule c. Compute

homogeneity of variance assumption

1. Describe the general characteristics of a research study for which an independent-measures t would be the appropriate test statistics 2. What is measured by the estimated standard error that is used for the independent-measures t statistic? 3. Describe the homogeneity of variance assumption, and explain why it is import

Statistical Analysis of Quaker Oats

Quaker Oats is contemplating changing the shape of its box from the quaint cylinder presently in use. Different random samples were selected from five stores of similar size in the same region, and one of the candidate boxes was substituted for the cylinder for several days. The following results were obtained for the total numb

Various Statistics Questions

1. Based on the specific question under study, how can one always determine which is the null hypothesis (H0) and which is the alternative hypothesis (H1). 2. A consumer advocate tests the claim that the Toyota Corolla actually delivers less than 32 mpg (as stated on the advertisements). So, we have:

Statistics - True and False

1. Degrees of freedom for the independent-measures t statistic can be computed as df = n 1 + n 2 - 2. True False 2. For an independent-measures study comparing two samples with n = 8 in each sample, the t statistic would have df = 15. True False 3. Which of the following rese

Single-tailed, 2-sample mean, t-test

Ten automobiles were driven on a measured test track - once with standard gasoline with no additive and once with an additive supposed to increase miles per gallon (mpg). The results are given below: mpg / car # 1 2 3 4 5 6 7 8 9 10 without additive 19 22 25 18 26 21 23 28 24 24 with additive