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Hypothesis Testing

Data Sets: T-tests vs. Z-tests

Perform hypothesis testing on one variable's data. (Choose either the intrinsic or extrinsic column.) Perform a t-test by formulating a null and an alternative statement, choosing an acceptable significance value, determining the appropriate critical value, selecting the test statistic and determining its value from the sample d

Statistics - Hypothesis tests...

Hypothesis tests for the correlation coefficient and the slope of the least-squares regression line The Cadet is a popular model of sport utility vehicle, known for its relatively high resale value. For a random sample of Cadets, each bought "new" two years ago and each sold "used" within the past month, the sample correlatio

Statistics of Plant Heights

Heights were measured for a random sample of 20 plants grown while being treated with a particular nutrient. The sample mean and sample standard deviation of those height measurements were 39 centimeters and 12 centimeters, respectively. Assume that the population of heights of treated plants is normally distributed with mea

Statistics - Hypothesis Testing (Z-Testing).

4. The average monthly cot for a studio apartment in NYC is reported to be $1,000. You want to prove that average monthly rent is not what is stated. You collect a random sample of 25 rents in all areas and find that the sample mean is $961 and the sample standard deviation is $110. Can you disprove the claim at the 

Hypothesis Testing (Z-Testing)

A doctor suspected that smokers between 40 and 50 with lung disease had been smoking on average more than 20 years. A sample of 10 smokers gave the following results: 22 2 19 25 24 26 23 2 21 22 Using a 1% significance level is there sufficient evidence to justify the doctors belief? Is there sufficient evidence t

Statistics: Testing the Null Hypothesis

Please show all calculations on every problem. 1. A machine produces 3-inch nails. A sample of 12 nails was selected and the lengths determined. The results are as follows: 2.89 2.95 3.00 3.05 2.99 2.96 3.10 3.06 3.00 3.12 3.00 2.95 Use these results to test H0: u = 3 and Ha: u does not = 3 at alpha = 0.05. Give the crit

Conducting a One-Tail Hypothesis Test

Given the following data from two independent data sets, conduct a one-tail hypothesis test to determine if the means are statistically equal using alpha=0.05. Do not do a confidence interval. n1 = XX n2 = XX xbar1= XXXX xbar2 = XXXX s1=XXX s2 = XXX

Samples, Testing, and Variables

1. Classify the following as independent or dependent samples: a. The effectiveness of two blood pressure medicines on two groups of patients. b. Measures of gas mileage and speed for a group of race cars. c. Scores of a group of nurses on the NCLEX nursing license exam. 2. Please answer the following. a. Explain the d

Statistics - Null and Alternate Hypothesis.

1. The null hypothesis Ho: 2. The alternate hypothesis H1: 3. The type of test statistic __ (F, Z, chi square t) degrees of freedom __ 4. The value of the test statistic: round to at least three decimal places 5. the p-value (round to at least three decimal places) 6. Based on the data, can the professor conclude (using th

Hypothesis testing problems

1. Classify the following as independent or dependent samples: a. The effectiveness of two blood pressure medicines on two groups of patients. b. Measures of gas mileage and speed for a group of race cars. c. Scores of a group of nurses on the NCLEX nursing license exam. 2. Please answer the following. a. Explai

Estimation and Test of Hypothesis

1. When the means of two unrelated samples are used to compare two populations, we are dealing with two dependent means ___ T/F 2. If standard deviation is unknown when completing a hypothesis test about the population mean, then the best estimate for the unknown standard deviation is s. _____ T/F 3. The number of d

P-value for Fast Food Companies

1. Determine the p-value for H0: p=.5 versus HA: p =/ (difference) .5 when n=225 and p^ =.54. 2. A fast food company uses two management-training methods. Method 1 is a traditional method of training and Method 2 is a new and innovative method. The company has just hired 36 new management trainees. 15 of the trainees are

Significance Level for Accompanying Data

The accompanying data are the times in seconds that it took a sample of employees to assemble a component at Ental Industries manufacturing facility. Assembly times are normally distributed. At the .05 significance level, can we conclude that the mean assembly time for this component is not equal to 3 minutes? Use HA: 

Statistics - Hypothesis..

1. is the data normally distributed? (use the formula for pearson index) 2.the average cholesterol should be less than or equal to 200. Does the above data support this hypothesis if a =.10? 1. Find Q1, Q2, Q3 (quartiles) 2.is the data normally distributed (use the formula for pearson index) 3.come up with a hypot

Two-Tail Hypothesis Testing and Confidence Intervals

1. A certain type of cable was advertised as having a breaking strength of 1000 pounds. A test of XX pieces of this cable was conducted and the mean breaking strength of this sample was XXX pounds with a sample standard deviation of XX pounds. Conduct a two-tail hypotheses test at alpha = .05 to determine if this sample data pro

Significance Levels, P-Values, and Confidence Intervals

You are investigating the flight characteristics of different kinds of birds. You collect a sample of 33 European swallows (Hirundo rustica) and measure their air-speed velocity in a borrowed wind tunnel. You find the mean air-speed velocity to be 11 meters/second with a standard deviation of 3 meters/second. You then collect a

Mean

A sample of 25 concession stand purchases at the October 22 matinee of Bride of Chucky showed a mean purchase of $5.29 with a standard deviation of $3.02. For the October 26 evening showing of the same movie, for a sample of 25 purchases the mean was $5.12 with a standard deviation of $2.14. The means appear to be very close,

Hypotheses

Does lovastatin (a cholesterol-lowering drug) reduce the risk of heart attack? In a Texas study, researchers gave lovastatin to 2,325 people and an inactive substitute to 2,081 people (average age 58). After 5 years, 57 of the lovastatin group had suffered a heart attack, compared with 97 for the inactive pill. (a) State the

Statistical Tests, Hypothesis Testing, p-Values, and Sample Size

1. Classify the following as independent or dependent samples: a. The effectiveness of two blood pressure medicines on two groups of patients. b. Measures of gas mileage and speed for a group of racecars. c. Scores of a group of nurses on the NCLEX nursing license exam. 2. Please answer the following. a. Expla

Salary equity study of faculty at a certain university

#1 in a salary equity study of faculty at a certain university, the salaries of 50 male assistant professors showed a sample mean of $36,400 with a sample standard deviation of 360, whereas the salaries of 50 female assistant professors chosen independently showed a sample mean of $34,200 with a sample standard deviation of 220.

Hypothesis Testing Problems and Confidence Intervals

1. A study was conducted to estimate the mean amount spent on birthday gifts for a typical family having two children. A sample of 175 was taken, and the mean amount spent was $250. Assuming a standard deviation equal to $45, find the 95% confidence interval for mu, the mean for all such families. 2. What sample size would b

Null Hypothesis of M&M colors with ANOVA

The weights (in grams) of four different colors of M&M candies are given below, along with the mean weight and variance of each color, and the variance of the sample means. Use a one-way ANOVA at the 0.025 significance level to test the null hypothesis that the different color M&M candies have the same mean weight. Red Oran

Numerical Hypothesis Statement for Wages

Is the annual average wage of unmarried people (18 - 30) the same as that of married people (31 - 43)? Hypothesis Statements: H0: The mean annual wages of unmarried people (18 - 30) is the same as that of married people (31 - 43) Ha: The mean annual wages of unmarried people (18 - 30) is different from that of marrie

Biostatistics in Genstat

1. (a) The medical literature suggest that the probability of a child contracting chickenpox (A) is 0.18; of contracting German measles (B), 0.12; and of contracting both, 0.07. i. Are the two events A and B mutually exclusive? Independent? Explain. ii. Find the probability that a child will contract at least one of the t

Statistics - P Value

1. A college professor claims that the average cost of a textbook is greater than $27.50. A sample of 50 books has an average cost of $29.30. The standard deviation of the sample is $5.00. Find the p value for the test. On the basis of the p-value, should the null hypothesis be rejected at =.05 2. Use the traditional meth

In this solution, the solution calculations are done using Excel. There are four tests of hypothesis regarding the population mean, the four standard deviations of the four samples are compared, and upper and lower control limits for the process are calculated.

Quality Associates, Inc, a consulting firm, advises its clients about sampling and statistical procedures that can be used to control their manufacturing processes. In one particular application, a client gave Quality Associates a sample of 800 observations taken during a time in which that client's process was operating satisfa

Hypothesis Tests Multiple Choice

See the attached file for the proper symbols and formatting. Part I T/F & Multiple Choice 1. An estimator is consistent if, as the sample size decreases, the value of the estimator approaches the value of the parameter estimated. ____ T/F 2. For a specific confidence interval, the larger the sample size, the smaller

Population Means testing :True for false question

Please indicate either TRUE or FALSE for the questions. If you indicate FALSE as your answer, briefly explain why the statement is false. 1. In order to compare the characteristics of two different populations, a sample should be extracted from each population. 2. When two populations are compared and samples taken fr

Hypothesis testing :True or false questions

Instructions: Please indicate either TRUE or FALSE for the questions. If you indicate FALSE as your answer, briefly explain why the statement is false. 1. In order to compare the characteristics of two different populations, a sample should be extracted from each population. 2. When two populations are compared and s