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
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
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
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
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
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
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
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
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: 
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
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
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
10.30 In Dallas, some fire trucks were painted yellow (instead of red) to heighten their visibility. During a test period, the fleet of red fire trucks made 153,348 runs and had 20 accidents, while the fleet of yellow fire trucks made 135,035 runs and had 4 accidents. At α = .01, did the yellow fire trucks have a significa
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,
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
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
#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.
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
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
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
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
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
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
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
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
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
1. Clark Heter is an industrial engineer at Lyons Products. He would like to determine whether there are more units produced on the night shift than on the day shift. Assume the population standard deviation for the number of units produced on the day shift is 21 and 28 on the night shift. A sample of 54 day-shift workers showed
1. In this test, the variance is known. Find the p-value of the test to 4 decimals, if the obtained value of the test statistic is 2.34. Make a sketch and represent the p-value. H_o : Mu = Mu_o H_a : Mu ,not = to, Mu_o 2. In this test, the variance is known. Find the p-value of the test to 4 decimals, if the obtained valu
1. In the following test, the variance is known. What is the rejection rule for the null hypothesis, if the level of significance is 0.06? H_o : Mu ,< equal to, Mu_o H_a : Mu > Mu_o Note: Your answer should be a sentence and include some specific value(s). 2. In the following test, the varianc
In 2001, the U.S. Department of Labor reported the average hourly earnings for U.S. production workers to be $14.32 per hour. A sample of 60 production workers during 2003 showed a sample mean of $14.68 per hour. Assuming the population standard deviation σ = $1.55, can we conclude that an increase occurred in the mean hourly e