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Get college assignment help at uniessay writers 1. Suppose the correlation between two variables x and y is due to the fact that both are responding to changes in some unobserved third variable. What is this due to? (a) Cause and effect between x and y (b) The effect of a lurking variable (c) Extrapolation (d) Common sense (e) None of the above. The answer is .

Problem 1 Richard has been given a 9-question multiple-choice quiz in his history class. Each question has three answers, of which only one is correct. Since Richard has not attended the class recently, he doesn’t know any of the answers. Assuming that Richard guesses on all 9 questions, find the probability that he will answer all questions incorrectly? Round your answer to the nearest thousandth. 1) 0.667 2) 0.500 3) 0.702 4) 0.026 5) 0.889 Problem 2 Richard has been given a 9-question multiple-choice quiz in his history class. Each question has five answers, of which only one is correct. Since Richard has not attended the class recently, he doesn’t know any of the answers. Assuming that Richard guesses on all 9 questions, find the probability that he will answer at least 5 questions correctly? Round your answer to the nearest thousandth. 1) 0.017 2) 0.500 3) 0.556 4) 0.111 5) 0.020 Problem 3 Richard has been given a 7-question multiple-choice quiz in his history class. Each question has five answers, of which only one is correct. Since Richard has not attended the class recently, he doesn’t know any of the answers. Assuming that Richard guesses on all 7 questions, find the probability that he will answer no more than 3 questions correctly? Round your answer to the nearest thousandth. 1) 0.115 2) 0.429 3) 0.967 4) 0.086 5) 0.500 2 Problem 4 The probability of a radar station detecting an enemy plane is 0.65 and the probability of not detecting an enemy plane is 0.35. If 20 stations are in use, what is the expected number of stations that will detect an enemy plane? 1) 20 2) 0 3) 18 4) 13 5) none of these choices Problem 5 The probability of a radar station detecting an enemy plane is 0.75. If 3 stations are in use, what is the standard deviation? Round your answer to nearest hundredth. a) 1.50 b) 0.75 c) 0.56 d) 2.25 e) none of these choices Problem 6 Suppose that on the leeward side of the island of Oahu, in the small village of Nanakuli, about 80% of the residents are of Hawaiian ancestry. Let n = 1, 2, 3,… represent the number of people you must meet until you encounter the first person of Hawaiian ancestry in the village of Nanakuli. Compute the probability for n = 3. Round your answer to the nearest ten thousandth. 1) 0.0420 2) 0.0320 3) 0.1280 4) 0.1380 5) 0.2330 Problem 7 Suppose that on the leeward side of the island of Oahu, in the small village of Nanakuli, about 50% of the residents are of Hawaiian ancestry. Let n = 1, 2, 3,… represent the number of people you must meet until you encounter the first person of Hawaiian ancestry in the village of Nanakuli. Compute the probability for n ³ 4. Round your answer to the nearest ten thousandth. 1) 0.1150 2) 0.0725 3) 0.0625 4) 0.1250 5) 0.3120 3 Problem 8 Suppose that on the leeward side of the island of Oahu, in the small village of Nanakuli, about 30% of the residents are of Hawaiian ancestry. Let n = 1, 2, 3,… represent the number of people you must meet until you encounter the first person of Hawaiian ancestry in the village of Nanakuli. What is the expected number of people you must meet until you encounter the first person of Hawaiian ancestry in the village of Nanakuli? Round your answer to the nearest hundredth. 1) 1.43 2) 3.44 3) 33.33 4) 33.55 5) 3.33 Problem 9 In one of the archaeological excavation sites, the artifact density (number of prehistoric artifacts per 10 liters of sediment) was 1.0. Suppose you are going to dig up and examine 50 liters of sediment at this site. Let r = 0, 1, 2, 3,… be a random variable that represents the number of prehistoric artifacts found in your 50 liters of sediment. Compute the probability that in your 50 liters of sediment you will find 3 prehistoric artifacts. Round your answer to the nearest ten thousandth. 1) 0.0351 2) 0.1755 3) 0.1514 4) 0.1744 5) 0.1404 Problem 10 In one of the archaeological excavation sites, the artifact density (number of prehistoric artifacts per 10 liters of sediment) was 1.0. Suppose you are going to dig up and examine 50 liters of sediment at this site. Let r = 0, 1, 2, 3,… be a random variable that represents the number of prehistoric artifacts found in your 50 liters of sediment. Find the probability that you will find fewer than 3 prehistoric artifacts in the 50 liters of sediment. Round your answer to the nearest ten thousandth. 1) 0.2650 2) 0.1247 3) 0.4405 4) 0.6160 5) 0.0517 4 Problem 11 In one of the archaeological excavation sites, the artifact density (number of prehistoric artifacts per 10 liters of sediment) was 2.0. Suppose you are going to dig up and examine 30 liters of sediment at this site. Let r = 0, 1, 2, 3,… be a random variable that represents the number of prehistoric artifacts found in your 30 liters of sediment. Find the probability that you will find 2 or more artifacts in the 30 liters of sediment. Round your answer to the nearest ten thousandth. 1) 0.9851 2) 0.9752 3) 0.0248 4) 0.9826 5) 0.0174 Problem 12 Assuming that the heights of college women are normally distributed with mean 68 inches and standard deviation 2.5 inches, what percentage of women are shorter than 63 inches? 1) 2.3% 2) 97.7% 3) 84.1% 4) 0.1% 5) 50.0% Problem 13 At a certain excavation site, archaeological studies have used the method of tree-ring dating in an effort to determine when people lived in there. Wood from several excavations gave a mean of (year) 1128 with a standard deviation of 44 years. The distribution of dates was more or less mound-shaped and symmetrical about the mean. Use the empirical rule to estimate a range of years centered about the mean in which about 99.7% of the data (tree-ring dates) will be found. 1) from 1128 to 1172 2) from 996 to 1040 3) from 996 to 1216 4) from 1040 to 1128 5) from 996 to 1260 Problem 14 Assume that x has a normal distribution, with the specified mean and standard deviation. Find the indicated probabilities. P(7 £ x £ 18); m = 17; s = 3 1) 0.999 2) 0.369 3) 0.001 4) 0.630 5) 1.000 5 Problem 15 Assume that x has a normal distribution, with the specified mean and standard deviation. Find the indicated probabilities. P(x ³15); m = 18; s = 3 1) 0.841 2) 0.171 3) 0.079 4) 0.421 5) 0.341 Problem 16 A researcher is interested in the lengths of Salvelinus fontinalis (brook trout), which are known to be approximately normally distributed with mean 80 centimeters and standard deviation 5 centimeters. To help preserve brook trout populations, some regulatory standards need to be set limiting the size of fish that can be caught. To ensure that the shortest 8% of the brook trout get thrown back the lower cutoff should be set at 1) 72.95 centimeters. 2) 75.00 centimeters. 3) 80.00 centimeters. 4) 87.03 centimeters. Use the following to answer problems 17–18. The amount of cholesterol in a person’s body produced by their liver and other cells is proposed to be normally distributed with mean 75% and standard deviation 0.5%. Problem 17 The probability that a person produces more than 76.7% of the cholesterol in their body is 1) 0.0003. 2) 0.0006. 3) 0.9997. 4) 1. Problem 18 The first quartile of the distribution of cholesterol production is 1) 74.66%. 2) 75.00%. 3) 75.34%. 4) 76.00%.

The mean score on the SAT Math Reasoning exam is 518. A test preparation company states that the mean score of students who take its course is higher than 518. Suppose a random sample of students taking the preparatory course is selected in order to test this, and a hypothesis test is conducted at the 5% level of significance. The test resulted in a p-value of .179. If in fact the true mean score of all students taking the preparatory course is 522, which of the following statements is true about our hypothesis test?

There are 10 rolls of film in a box and 3 are defective. Two rolls will be selected, one after the other. What is the probability of selecting a defective roll folloed by another defective roll?

3. A 95% confidence interval estimate for a population mean was computed to be (44.8 to 50.2). Determine the mean of the sample, which was used to determine the interval estimate. 4. In testing the hypothesis, H0: 28.7 and Ha: Part II. Short Answers

When a random sampling frame has a systematic pattern in the listing of sampling units, rather than a random pattern, A. a systematic sample must be drawn. B. the problem of periodicity exists. C. a random error occurs. D. a cluster sample must be used. E. a sampling frame error occurs

Chapter 11 33. The manufacturer of an MP3 player wanted to know whether a 10 percent reduction in price is enough to increase the sales of its product. To investigate, the owner randomly selected eight outlets, the MP3 player was sold at the regular price. Reported below is the number of units sold last month at the sampled outlets. At the .01 significance level, can the manufacturer conclude that the price reduction resulted in an increase in sales? Regular price 138 121 88 115 141 125 96 Reduced price 128 134 152 135 114 106 112 39. An investigation of the effectiveness of an antibacterial soap in reducing operating room contamination resulted in the accompanying table. The new soap was tested in a sample of eight operating rooms in the greater Seattle are during the last year. Operating Room A B C D E F G H BEFORE 6.6 6.5 9.0 10.3 11.2 8.1 6.3 11.6 AFTER 6.8 2.4 7.4 8.5 8.1 6.1 3.4 2.0 At the .05 significance level, can we conclude the contamination measurements are lower after use of the new soap? Chapter 12 23. The City of Maumee comprises four districts. Chief of Police Andy North wants to determine whether there is a difference in the mean number of crimes committed among the four districts. He recorded the number of crimes reported in each district for a sample of six days. At the .05 significance level, can the chief of police conclude there is a difference in the mean number of crimes? Number of Crimes Rec Center Key Street Monclova Whitehouse 13 21 12 16 15 13 14 17 14 18 15 18 15 19 13 15 14 18 12 20 15 19 15 18 31. Listed below are the weights (in grams) of a sample of M

6. Often in medical research, more than one group is doing work in the same area and report their results separately. It is of interest to be able to combine the results of multiple trials. Suppose that researchers at UZ carry out a trial of Treatment SX for psoriasis. They treat 20 patients and observe13 successes. Meanwhile over at UM the researchers have a di¤erent trial design for the sameTreatment SX. Patients are treated until they observe 5 successes. It turns out that it takes the UM group a total erollment of 20 patients to observe 5 successes. Researchers at UZ and UM are actually no longer on speaking terms after a recent collaboration in which they could not decide on authorship for a publication. So you may con dently assume that the trials are carried out independently. Moreover no patient is treated more than once. (a) Let X be the number of successes at UZ. What is the distribution of X? (b) Let Y be the number of patients enrolled at UM. What is the distri- bution of Y ? (c) Provide maximum likelihood estimates of individual success rates for the two trials? (d) Assume that the success rate of Treatment SX is identical for the two trials. Call this success rate p:Provide a maximum likelihood estimate of p. In other words how can you use maximum likelihood to combine the information from the two trials to get a single estimate of p (e) What is the asymptotic distribution of your estimate from (d)? I am not sure about part (e). The asymptotic variance of the combined p. Thanks!

About 12% of the population is hopelessly romantic. If two people are randomly selected, what is the probablity both are hopelessly romantic?

What is the probability that none of the lines experiences a surface finish problem in 43 hours of operation?

Get college assignment help at uniessay writers toss a fair coin until at least one head and one tail have been obtained. find the pmf of X, the number of tosses required.

About 39% of all U.S. adults will try to pad their insurance claims! Suppose that you are the director of an insurance adjustment office. Your office has just received 132 insurance claims to be processed in the next few days. Find the following probabilities.

Bowl I contains 7 red and 3 white chips and bowl II has 4 red and 6 white chips. Two chips are selected at random and without replacement from I and transferred to II. Three chips are then selected at random without replacement from II: i. What is the probability that all three are white? ii. Given that three white chips are selected from II, what is the probability that two white chips were transferred from I?

True or False…”The cross-tabulation of two survey questions (or variables) results in a contingency table.

Assume that the durations of 9-inning baseball games are uniformly distributed between 160 minutes and 240 minutes. What is the probability that a 9-inning game will last between 180 and 220 minutes?

In this portion of the SLP you will choose 3 or 5 articles from your literature review that specifically describe research done in your area of interest. You will briefly describe the research procedure, including who did the research, where and how the sample was obtained, what procedures the research entailed, and a description of the results. You will indicate in a brief summary paragraph which of your research studies seems to yield the most meaningful and valid results, and which seems to be the weakest or most questionable.

Which term is not typically included in the definition section of a quasi-experimental study parallel-equated groups Quasi-experimental external validity all of the above

last fall, a sample of n=36 freshman was selected to participate in a new 4-hour program. to evaluate the effectivenes, the sample was compared to the rest of the freshman class. the score of the class was u=74. students in the new program has a mean of M=79.4 with a standard deviation of s=18. use a one-tailed test with a=.05

X and Y has the joint density f(x,y)=exp(-y), 0<=x<=y a. Find covariance of x and y and the correlation of x and y. b. Find E(X|Y=y) and E(Y|X=x)

a fast food restaurant recently completed a study of the time to complete each order. it found that the average time to complete an order was 5.0 minutes with a standard deviation of 45 seconds (0.75 minutes). 1)what percent of orders are expected to take longer than 5.5 minutes to fill? 2)what percent of orders can be expected to be compleated in less than or equill to 4 minutes? 3)if we were to take the averages of the times to serve 20 customers, what would the expected average and standered deviation be? 4) determine the 95% range for the means of the times to serve 20 customers.

Specifications for a part of a DVD player state that the part should weigh between 24 and 25 ounces. The process that produces the parts yield a mean of 24.5 ounces and a standard deviation of .2 ounce. The distribution of output is normal. a. What percentage of parts will not meet the weight specs? b. Within what values will 95.44 percent of sample means of this process fall, if samples of n = 16 are taken and the process is in control (random)?

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November 3, 2019