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Student's t-Test

Students T-Test for Furniture Store Data

A furniture store claims that a specially ordered product will take, on average, M = 35 days (5 weeks) to arrive. The standard deviation of these waiting times is 8 days. We suspect that the special orders are taking longer than this. To test this suspicion, we track a random sample of 100 special orders and find that the orders

Statistics

A company implemented a safety program designed to reduce the number of work related injuries. Human Resources department collected the following data to verify the effectiveness of the program: Number of injuries per week Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8 Before 4 5 2 2

One sample t test for comparison of mean

6. The following data was collected on the thickness of glass being manufactured. The glass thickness is normally distributed. 0.262 0.256 0.263 0.223 0.251 0.238 0.184 0.248 0.189 0.204 0.217 0.255 0.240 0.197 0.237 0.265 0.275 0.236 0.225 0.234 0.261 0.296 a. If the manufacturer claimed that the glass was 0.250 inches thi

Palmer vs. Woods (Hypothesis Test of Two Means)

Arnold Palmer and Tiger Woods are two of the best golfers to ever play the game. The question was raised as to how these two golfers would have compared if both were playing at the top of their game. The following sample data show the results of 18-hole scores during a PGA tournament competition. Palmer's scores are from

Testing of Hypothesis

One sample t test, Independent sample t test, Z test for population proportion . See attached file for full problem description.

Two sample Hypothesis Test - t-statistic

Question : A double blind study was carried out to determine whether a certain calcium supplement reduces systolic blood pressure in adult black males. One group of 16 took the calcium supplement and a control group of 14 received a placebo. The summary statistics for the decrease in blood pressure were as follows: Group

Statistic Problem

1) We wish to estimate the average daily yield of a chemical manufactured in a chemical plant. The mean daily yield was recorded for 50 days, and found to be 871 tons/day. The standard deviation turned out to be 21 tons. Test the null hypothesis that the average daily yield of the chemical is 880 tons at . 2) Given the

One-tail T Testing and Stating Hypotheses

T test to evaluate one set of data points with another set of data points (Use t test testing to evaluate which set of data points (population) will have a larger mean difference). I need help with evaluating the information and stating the hypotheses and the final decision (to reject or fail to reject H0). Some of the informati

Statistics - Two Tailed Hypothesis Test for One Sample

Question: A claim is made that the mean height of police officers is 5feet 11inches. To test whether this claim is true or not, a random sample of 25 police officers was gathered. This sample had a mean height of 5 feet 10inches with s=3inches. Test at the 5% significance level

Statistics Hypothesis Test, Small Samples One Tailed Test

Question The average IQ of a group of researchers is quoted to be 260. Thinking that this figure is too large, consulting firm tested a random sample of 8 researchers and found that the average IQ was 250 with s=8. Test at a level of significance of 1%.

Political Statistics

A. A study examines self-esteem and depression in children. A sample of 25 children with low self- esteem is given a standardized test for depression. The average score for the group is M = 93.3. For the general population, scores on the depression test form a normal distribution with a mean of Mu = 90 and a standard deviat

Interpreting Data

The assignment starts out by stating, you are given the responsibility fo presenting the results of a yearlong study of a teaching strategy to the school board. Fifty-two students were chosen at random from the school population to participate in the study. Twenty-six students were then randomly chosen to serve as a control gr

Glucose Level, Total Cost and LOS, Waiting Time

1. You want to test the effectiveness of a new diabetes management program on lowering fasting blood sugar (glucose) levels for individuals who have diabetes. Background: According to information found on the internet, the following are glucose level ranges and their associated meaning: Glucose Level (mg/dL) Test Resu

T-Test, Effect Size, Power

For this exercise, let's assume that you are setting up this study, rather than being called in after the fact. A review of the clinic's records indicates that their 8-week diet produces an average weight loss of 3.1 kg, with a standard deviation of  2.4 kg. If we desire to measure a large effect (Cohen's d  0.8)

SPSS computation and interpretation (T-Test) Help

SPSS computation and interpretation (T-Test) Rental card gasoline prices per gallon were sampled at eight major airports. Data for Hertz and National car rental companies follow: Airport Hertz National Boston Logan 1.55 1.56 Chicago O'Hare 1.62 1.59 Los Angeles 1.72 1.78 Miami 1.65 1.49

Paired Students t test.

Please explain and resolve the attached problem. Thanks! Assume that you want to test the claim that the paired sample data come from a population for which the mean difference is = 0. Compute the value of the t test statistic. x 7 2 7 3 10 y 4 4 3 4 5 Use three decimal places

Independent sample t test for comparison of travel cost

Ms Moline is the budget director for Nexus Media Inc. She is comparing travel costs for sales and the audit staff. She collected the following sample data: Sales Audit 131 130 135 102 146 129 165 143 136 149 142 120 139 At the .10 level of significance can she conclude that the daily expenses are greater for the

Comparison of populations mean: Students t test

The Commercial Bank and Trust Company is studying the use of its automatic teller machines (ATMs). Of particular interest is whether young adults (under 25 years) use the machines more than senior citizens. To investigate further, samples of customers under 25 years of age and customers over 60 years of age were selected. The nu

Choosing between a Z and T test

You are concerned about wait times at the cash registers in the supermarket. You collect data and have a sample size of 10, which test would you use a Z or a T test and why? What is the major difference between a Z and a T test. (hint sample size and variability)

Independent sample t test for solar energy data

Solar Energy in Different Weather: A student of the author lives in a home with a solar electric system. At the same time each day, she collected voltage readings from a meter connected to the system and the results are listed in the accompanying table. Use a).05 significance level to test the claim that the mean voltage reading

T Test - Testing of hypothesis using five step procedure

1. The new director of special programs in XYZ Corporation felt the customers were waiting too long to receive and complete forms needed to enroll in special programs. After collecting some data, Ms. Jones determined the mean wait time was 28 minutes. She felt this time period was excessive and she instituted new procedures to s