Concept explainers
a.
Find the least-squares regression line to predict the weights from heights.
a.

Answer to Problem 23E
The least-squares regression line to predict the weights from heights is
Explanation of Solution
Calculation:
The heights (inches) and weights (pounds) for some quarterbacks at a Combine are given.
Denote the heights as x and the weights as y.
Least-squares regression:
For an ordered pairs of values of variables, (x, y) with respective means
Regression:
Software procedure:
Step by step procedure to obtain regression using Minitab software is given as,
- Choose Stat > Regression > Regression > Fit Regression Model.
- In Responses, enter the numeric column containing the response data y.
- In Continuous Predictors, enter the numeric column containing the predictor variable x.
- Choose Results, select Regression equation and click OK.
- Click OK.
Output using MINITAB software is given below:
From the output, the least-squares regression line for the data set is found to be
b.
Explain whether it is possible to give an interpretation of the y-intercept of the regression line.
b.

Answer to Problem 23E
It is not possible to give an interpretation of the y-intercept of the regression line.
Explanation of Solution
Calculation:
Comparing the least-squares regression equation,
The y-intercept would mean that when the height of a quarterback is
However, it is practically impossible for the height of a quarterback to be 0 inches. The height would always take some non-zero positive value.
Hence, it is not possible to give an interpretation of the y-intercept of the regression line.
c.
Find the predicted difference in the weights of two quarterbacks, if their heights differ by 2 inches.
c.

Answer to Problem 23E
The predicted difference in the weights of two quarterbacks, if their heights differ by 2 inches is 3.18 pounds.
Explanation of Solution
Interpretation:
It is known that when the predictor variable values differ by the amount d, the corresponding response variable values differ by amount
Here,
From part a, the least-squares regression equation is:
Comparing this equation with the general form of the regression equation,
Thus,
Hence, the predicted difference in the weights of two quarterbacks, if their heights differ by 2 inches is 3.18 pounds.
d.
Find the weight of a quarterback whose height is 74.5 inches.
d.

Answer to Problem 23E
The weight of a quarterback whose height is 74.5 inches is 225.755 pounds.
Explanation of Solution
Calculation:
From part a, the least-squares regression equation is:
For a quarterback whose height is 74.5 inches,
Hence, the weight of a quarterback whose height is 74.5 inches is 225.755 pounds.
e.
Find whether the actual weight of Geno Smith is more or less than his predicted weight.
e.

Answer to Problem 23E
The actual weight of Geno Smith is less than his predicted weight.
Explanation of Solution
Calculation:
The actual height of Geno Smith is 74 inches and his actual weight is 218 pounds.
For Geno Smith, height is 74 inches, that is,
It is observed that the predicted weight of Geno Smith is 224.96 pounds, which is greater than his actual weight of 218 pounds.
Hence, the actual weight of Geno Smith is less than his predicted weight.
Want to see more full solutions like this?
Chapter 11 Solutions
ALEKS 360 ESSENT. STAT ACCESS CARD
- Consider the hypothesis test Ho: = 622 against H₁: 6 > 62. Suppose that the sample sizes are n₁ = 20 and n₂ = 8, and that = 4.5; s=2.3. Use a = 0.01. (a) Test the hypothesis. Round your answers to two decimal places (e.g. 98.76). The test statistic is fo = i The critical value is f = Conclusion: i the null hypothesis at a = 0.01. (b) Construct the confidence interval on 02/022 which can be used to test the hypothesis: (Round your answer to two decimal places (e.g. 98.76).) iarrow_forward2011 listing by carmax of the ages and prices of various corollas in a ceratin regionarrow_forwardس 11/ أ . اذا كانت 1 + x) = 2 x 3 + 2 x 2 + x) هي متعددة حدود محسوبة باستخدام طريقة الفروقات المنتهية (finite differences) من جدول البيانات التالي للدالة (f(x . احسب قيمة . ( 2 درجة ) xi k=0 k=1 k=2 k=3 0 3 1 2 2 2 3 αarrow_forward
- 1. Differentiate between discrete and continuous random variables, providing examples for each type. 2. Consider a discrete random variable representing the number of patients visiting a clinic each day. The probabilities for the number of visits are as follows: 0 visits: P(0) = 0.2 1 visit: P(1) = 0.3 2 visits: P(2) = 0.5 Using this information, calculate the expected value (mean) of the number of patient visits per day. Show all your workings clearly. Rubric to follow Definition of Random variables ( clearly and accurately differentiate between discrete and continuous random variables with appropriate examples for each) Identification of discrete random variable (correctly identifies "number of patient visits" as a discrete random variable and explains reasoning clearly.) Calculation of probabilities (uses the probabilities correctly in the calculation, showing all steps clearly and logically) Expected value calculation (calculate the expected value (mean)…arrow_forwardif the b coloumn of a z table disappeared what would be used to determine b column probabilitiesarrow_forwardConstruct a model of population flow between metropolitan and nonmetropolitan areas of a given country, given that their respective populations in 2015 were 263 million and 45 million. The probabilities are given by the following matrix. (from) (to) metro nonmetro 0.99 0.02 metro 0.01 0.98 nonmetro Predict the population distributions of metropolitan and nonmetropolitan areas for the years 2016 through 2020 (in millions, to four decimal places). (Let x, through x5 represent the years 2016 through 2020, respectively.) x₁ = x2 X3 261.27 46.73 11 259.59 48.41 11 257.96 50.04 11 256.39 51.61 11 tarrow_forward
- If the average price of a new one family home is $246,300 with a standard deviation of $15,000 find the minimum and maximum prices of the houses that a contractor will build to satisfy 88% of the market valuearrow_forward21. ANALYSIS OF LAST DIGITS Heights of statistics students were obtained by the author as part of an experiment conducted for class. The last digits of those heights are listed below. Construct a frequency distribution with 10 classes. Based on the distribution, do the heights appear to be reported or actually measured? Does there appear to be a gap in the frequencies and, if so, how might that gap be explained? What do you know about the accuracy of the results? 3 4 555 0 0 0 0 0 0 0 0 0 1 1 23 3 5 5 5 5 5 5 5 5 5 5 5 5 6 6 8 8 8 9arrow_forwardA side view of a recycling bin lid is diagramed below where two panels come together at a right angle. 45 in 24 in Width? — Given this information, how wide is the recycling bin in inches?arrow_forward
- 1 No. 2 3 4 Binomial Prob. X n P Answer 5 6 4 7 8 9 10 12345678 8 3 4 2 2552 10 0.7 0.233 0.3 0.132 7 0.6 0.290 20 0.02 0.053 150 1000 0.15 0.035 8 7 10 0.7 0.383 11 9 3 5 0.3 0.132 12 10 4 7 0.6 0.290 13 Poisson Probability 14 X lambda Answer 18 4 19 20 21 22 23 9 15 16 17 3 1234567829 3 2 0.180 2 1.5 0.251 12 10 0.095 5 3 0.101 7 4 0.060 3 2 0.180 2 1.5 0.251 24 10 12 10 0.095arrow_forwardstep by step on Microssoft on how to put this in excel and the answers please Find binomial probability if: x = 8, n = 10, p = 0.7 x= 3, n=5, p = 0.3 x = 4, n=7, p = 0.6 Quality Control: A factory produces light bulbs with a 2% defect rate. If a random sample of 20 bulbs is tested, what is the probability that exactly 2 bulbs are defective? (hint: p=2% or 0.02; x =2, n=20; use the same logic for the following problems) Marketing Campaign: A marketing company sends out 1,000 promotional emails. The probability of any email being opened is 0.15. What is the probability that exactly 150 emails will be opened? (hint: total emails or n=1000, x =150) Customer Satisfaction: A survey shows that 70% of customers are satisfied with a new product. Out of 10 randomly selected customers, what is the probability that at least 8 are satisfied? (hint: One of the keyword in this question is “at least 8”, it is not “exactly 8”, the correct formula for this should be = 1- (binom.dist(7, 10, 0.7,…arrow_forwardKate, Luke, Mary and Nancy are sharing a cake. The cake had previously been divided into four slices (s1, s2, s3 and s4). What is an example of fair division of the cake S1 S2 S3 S4 Kate $4.00 $6.00 $6.00 $4.00 Luke $5.30 $5.00 $5.25 $5.45 Mary $4.25 $4.50 $3.50 $3.75 Nancy $6.00 $4.00 $4.00 $6.00arrow_forward
- MATLAB: An Introduction with ApplicationsStatisticsISBN:9781119256830Author:Amos GilatPublisher:John Wiley & Sons IncProbability and Statistics for Engineering and th...StatisticsISBN:9781305251809Author:Jay L. DevorePublisher:Cengage LearningStatistics for The Behavioral Sciences (MindTap C...StatisticsISBN:9781305504912Author:Frederick J Gravetter, Larry B. WallnauPublisher:Cengage Learning
- Elementary Statistics: Picturing the World (7th E...StatisticsISBN:9780134683416Author:Ron Larson, Betsy FarberPublisher:PEARSONThe Basic Practice of StatisticsStatisticsISBN:9781319042578Author:David S. Moore, William I. Notz, Michael A. FlignerPublisher:W. H. FreemanIntroduction to the Practice of StatisticsStatisticsISBN:9781319013387Author:David S. Moore, George P. McCabe, Bruce A. CraigPublisher:W. H. Freeman





