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Hypothesis Testing

Testing a claim in regards to a mean weight using a confidence level.

A flour manufacturer packs flour into paper bags, each of which is supposed to hold 10 pounds, or 160 ounces. Some customers have complained that the bags hold only 9.5 pounds, or 152 ounces. A test is conducted to determine whether the complaint is warranted. The weight of each bag is normally distributed with a Population Stan

Testing a claim using confidence levels.

A computer store claimed that about 80% of all service calls are due to a malfunctioning processor. A sample of 100 service calls is randomly selected and it is found that 70 are due to malfunctioning of processors. Determine the 99% confidence interval for the true proportion of all service calls that are due to the malfunction

Phstat clarification

Please solve these problems by using Excel's add-in called PhStat. What this means is that if you have the add-in, you use it (in excel) for the calculations and then cut n paste them into word. If you DON'T have it, you can download and install it from here: If you have trouble install

Math question

Context: It would normally follow on from work on setting up and testing hypotheses, and statistical analysis. Question: Suresh is comparing magazines and newspapers. He chooses a passage from one newspaper and one magazine. They each contain 100 words and he counts the lengths of all the words. now this is what you have to do o

Test the Null Hypothesis Using a Single-Sample Test

A cereal company claims that the average weight of its cereal packages is 14 ounces. Eight packages are tested and the weights given below are measured. Test the claim at α=.0.01 14.6, 13.8, 14.1, 13.7, 14.0, 14.4, 13.6, 14.2

Test the Claim

7 of 8,500 people vaccinated against a disease, later developed the disease. 18 out of 10,000 people after being vaccinated with a placebo(false vaccination), later developed the disease. Test the claim the vaccination helps lower the disease rate. Use a Type I error of 0.02. Please show all steps and use traditional metho

Test the Claim

A test of statistical reasoning is given to 10 students before and after an elementary statistics course. At V = 0.05, test the claim that the mean score is not affected by the course. Assume the students are randomly selected from normally distributed populations. BEFORE: 74 83 75 88 84 63 93 84 91 77 AFTER:

Hypothesis Testing

Test the claim the : = 74.1 at V = 0.01 where n = 14, sample mean is 79.0 and sample standard deviation is 5.6. Please explain by using the traditional methods for testing hypotheses and showing the results of all steps in the process.

Hypothesis Testing

The Boston Weather Services (BWS) says that the mean high temperature for October in a city is 56E F. You believe that it is lower. A sample of 31 mean October temperatures yields mean 54.0E F and standard deviation 5.6 E F. Test the BWS claim at V = 0.01.

Testing a claim from a data set.

Use the data set below to test the claim that more than 50% of the are at least 415. data set 350,527,480,410,360,470,390,510,430,452,341,385,380,409,500,377,400,380,420,460

Statistical significance: hypothesis testing regarding one mean

In the context of hypothesis testing regarding one mean, the test (Z or t) may be statistically significant at the 5% level, but not significant in a practical sense at all. Illustrate the meaning of this statement by citing 3 examples from any area of interest.

Hypothesis testing

Independent random samples taken at two companies provide the following information regarding the anual salaries of the employees. WhitneyCo. Max Co. sample size 72 50 Sample mean (in$1000) 48 43 Sample standard deviatio

Hypothesis testing

MNM Inc, has their stores located at three different locations. Random samples of the daily sales of the three stores (in $1,00) are shown below. Stores 1 store 2 store 3 9 10 6 8 11 7 7 10 8

Present and justify hypotheses

I need to present and briefly justify four hypotheses involving relation between pairs of variables, using the same variable as dependent. The variables I would like to use are: Immigr (DV) Income, education, and age (IV) Can you help me with this problem? Thank you,

Unusual Result

A candy company claims that 92% of consumers like their candies. To test this claim, 9571 people are selected at random from those who have eaten the company's candies. 791 rate the candies as unsatisfactory. Is this an unusual result (show criterion for determining the answer to this question)? Also, how do you interpret your s

Applying Statistical Tests

I would like to compare data from a study I have been doing, but don't know which statistical tests to use. I have surveyed 40 hedgerows: 20 from site 1 20 from site 2 I have attached some of the data to show you at what stage I'm at: 1). I need to find out the significance of difference between the 2 sites in terms of