Concept explainers
i.
To identify:
The independent variable x1,x2,x3 used for prediction of y
i.

Answer to Problem 13.4E
Independent variable x1,x2,x3 contribute the information to predict y ,
Explanation of Solution
Given information:
b0=1.04b1=1.29SE(b1)=0.42b2=2.72SE(b2)=0.65b3=0.41SE(b3)=0.17
Formula used:
The student’s t- statistics is given by the following expression:
t=bi−βtSE(bi)
The values:
(t≤3.0714)=0.9947(t≤4.1846)=0.9992(t≤2.4117)=0.9827
Calculation:
To identify which independent variable x1,x2,x3 contribute the information to predict y , need to use the significance of partial regression co-efficient.
The F test with the hypothesis:
To test the null hypothesis:
H0:βt=0
Vs
H0:βt≠0
And, df=(n−k−1)=15−3−1=11
1. At b1=1.29,SE(b1)=0.42:
The student’s t- statistics is calculated as:
t=b1−β1SE(b1)t=0.129−00.42t=3.071428
The corresponding P -value is calculated as:
2P(t≥3.0714)=2P(1−(t≤300714))2P(t≥3.0714)=2P(1−0.9947)2P(t≥3.0714)=2(0.0053)2P(t≥3.0714)=0.0106
Reject the null hypothesis H0 as the P−value=0.0106 is less than α=0.05
Hence, independent variable x1 contribute the information to predict y .
2. At b2=2.72,SE(b2)=0.65:
The student’s t- statistics is calculated as:
t=b2−β2SE(b2)t=2.72−00.65t=4.1846
The corresponding P -value is calculated as:
2P(t≥4.1846)=2P(1−(t≤4.1846))2P(t≥4.1846)=2P(1−0.9992)2P(t≥4.1846)=2(0.0008)2P(t≥4.1846)=0.0016
Reject the null hypothesis H0 as the P−value=0.0016 is less than α=0.05
Hence, independent variable x2 contribute the information to predict y .
3. At b3=0.41,SE(b3)=0.17:
The student’s t- statistics is calculated as:
t=b3−β3SE(b3)t=0.41−00.17t=2.4117
The corresponding P -value is calculated as:
2P(t≥2.4117)=2P(1−(t≤2.4117))2P(t≥2.4117)=2P(1−0.9827)2P(t≥2.4117)=2(0.0173)2P(t≥2.4117)=0.0346
Reject the null hypothesis H0 as the P−value=0.0346 is less than α=0.05
Hence, independent variable x3 contribute the information to predict y .
Conclusion:
Therefore, all independent variable x1,x2,x3 contribute the information to predict y .
ii.
The least-square prediction equation
ii.

Answer to Problem 13.4E
The least-square prediction equation is Y=1.04+1.29x1+2.72x2+0.41x3
Explanation of Solution
Given information:
b0=1.04b1=1.29SE(b1)=0.42b2=2.72SE(b2)=0.65b3=0.41SE(b3)=0.17
Calculation:
The line which makes the vertical distance from the data points to the regression line is known as least-square regression. This distance is as small as possible.
The least-square prediction equation is given by the following eq:
ˆy=b0+b1x1+b2x2+b3x3
Put the given values:
ˆy=b0+b1x1+b2x2+b3x3ˆy=1.04+1.29x1+2.72x2+0.41x3
Conclusion:
Hence, least-square prediction equation is derived as ˆy=1.04+1.29x1+2.72x2+0.41x3
iii.
To explain:
The relationship between lines shown by the graph the relationship between x1 and y when (x2=1,x3=0) and (x2=1,x3=0.5)
iii.

Answer to Problem 13.4E
Lines shown by the graph is appearing to be parallel with each other
Explanation of Solution
Given information:
Predictor variables: x1,x2,x3
Calculation:
The given equation is ˆy=b0+b1x1+b2x2+b3x3 related to three predictor variables x1,x2,x3 .
When (x2=1,x3=0) the equation becomes:
ˆy=b0+b1x1+b2x2+b3x3ˆy=1.04+1.29x1+2.72x2+0.41x3ˆy=1.04+1.29x1+2.72(1)+0.41(0)ˆy=3.76+1.29x1
When (x2=1,x3=0.5) the equation becomes:
ˆy=b0+b1x1+b2x2+b3x3ˆy=1.04+1.29x1+2.72x2+0.41x3ˆy=1.04+1.29x1+2.72(1)+0.41(0.5)ˆy=3.965+1.29x1
The below graph depicting the relationship between x1 and y when (x2=1,x3=0) and (x2=1,x3=0.5)
Two lines shown by graph are seems to be parallel with each other.
Conclusion:
The above graph depicting the relationship between the two lines and they appear to be parallel to each other.
iv.
To explain:
The practical interpretation of β1
iv.

Answer to Problem 13.4E
The measurement of changes in x1when all other independent variables are held to be constant is done byβ1.
Explanation of Solution
Three-dimensional extension line of means is depicted by the given eq.
E(y)=β0+β1x1+β2x2
When x1 and x2 both are zero, the intercept-the average value of y is given by β0
Partial slopes of the model is denoted by β1 and β0 . They are also known as partial regression coefficients.
The measurement of changes occurs in y for one unit change in x1 when all other independent variables are held to be constant is done by β1 .
The slope estimated by a fit line with x1 alone is not same as partial regression coefficients β1 with x1 and x2 .
Conclusion:
Hence, the unknown constant values are estimated by using the sample data.
Want to see more full solutions like this?
Chapter 13 Solutions
EP INTRODUCTION TO PROBABILITY+STAT.
- This is the information about the actors who won the Best Actor Oscar: Best actors 44 41 62 52 41 34 34 52 41 37 38 34 32 40 43 56 41 39 49 57 35 30 39 41 44 41 38 42 52 51 49 35 47 31 47 37 57 42 45 42 44 62 43 42 48 49 56 38 60 30 40 42 36 76 39 53 45 36 62 43 51 32 42 54 52 37 38 32 45 60 46 40 36 47 29 43 a. What is the variable? What type? b. Construct an interval-frequency table, with columns containing: class mark, absolute frequency, relative frequency, cumulative frequency, cumulative relative frequency, and percentage frequency.arrow_forwardans c plsarrow_forwardCritically analyze the following graph and, based on statistical information, indicate the type of error it presents IN NO MORE THAN 3 LINES SCOTCEN POLL OF POLLS SHOULD SCOTLAND BE INDEPENDENT? NO 52% YES 58% LIVE CAW NAS & 28.30 HAS KILLED MORE THAN 2,600 IN WEST AFRICA, WORLD HEALTH ORG. BROOKEBCNNarrow_forward
- Critically analyze the following graph and, based on statistical information, indicate the type of error it presents IN NO MORE THAN 3 LINES PRESIDENTIAL PREFERENCES RODOLFO CARTER 3% (+2pts) EVELYN MATTHEI 22% (+6pts) With the exception of President Boric, could you tell me who you would like to be the next president of Chile? CAMILA VALLEJO 4% (+2pts) JOSÉ ANTONIO KAST 19% (+5pts) MICHELLE BACHELET 6% (+1pts)arrow_forwardCritically analyze the following graph and, based on statistical information, indicate the type of error it presents IN NO MORE THAN 3 LINES 13% APPROVE 4% DOESN'T KNOW DOESN'T RESPOND 5% NEITHER APPROVES NOR DISAPPROVES 78% DISAPPROVES SURVEY PRESIDENTIAL APPROVAL DROPS TO 13%arrow_forwardPlease help with this following question I'm not too sure if question (a) and (b) are correct and not sure how to calculate (c) The csv data is below "","New","Current" "1","67",66 "2","77",73 "3","76",73 "4","76",76 "5","77",79 "6","84",76 "7","71",78 "8","84",72 "9","73",76 "10","71",73 "11","72",77 "12","70",72 "13","75",72 "14","84",71 "15","77",73 "16","65",72 "17","69",73 "18","71",73 "19","79",71 "20","75",78 "21","76",69 "22","73",74 "23","76",71 "24","64",74 "25","81",78 "26","79",76 "27","70",77 "28","79",71 "29","84",73 "30","79",69 "31","69",72 "32","81",76 "33","77",70 "34","77",71 "35","71",69 "36","67",72 "37","70",76 "38","77",73 "39","82",73 "40","72",73arrow_forward
- Please help me answer the following question(c) A previous study found that 15% of nurses reported participating in mental health support programs.From the 96% found in (b) , can you conclude that proportion of nurses reported participating in mental health support programs p(current), has changed from the previous study?(Yes/No) because the confidence interval in (b) (captures/does not capture) 15%.(d) Refer to your answer in (b) : The Alberta Nurses Association expects that not more than 23 % of nurses will participate in the survey on mental health support programs. Given the result in part (b) can we conclude that this expectation is reasonable?(Yes/No) because the (upper bound/lower bound) of the 96% confidence interval is (less than/not less than/greater than) 23%. The Alberta Nursing Association conducts an annual survey to estimate the proportion of nurses who participate in mental health support programs. The most recent application of this survey involved a random sample of…arrow_forwardPlease help me solve this questionThis is what was in the csv file:"","Diabetic","Heart Disease""1",32644,30646"2",789,1670"3",12802,36274"4",2177,5011"5",1910,3300"6",3320,4256"7",61425,39053"8",19768,28635"9",19502,39546"10",5642,12182"11",107864,152098"12",29918,60433"13",2397,3550"14",41559,34705"15",49169,57948"16",72853,83100"17",2155,2873"18",140220,134517"19",28181,26212"20",18850,38637"21",69564,68582"22",13897,12613"23",6868,9138"24",9735,4767"25",12102,13447"26",36571,50010"27",44665,55141"28",26620,33970"29",25525,29766"30",14167,20206Q(b) From this, the relationship between these two variables is (non-existent/positive/negative) . I can categorize this relationship as being (strong/weak/moderate).Q(c) Drop down is (+/-)Q(d) Drop downs in order are __% of the (average/median/variation/standard deviation) in the (the number of people diagnosed with heart disease/the number of people diagnosed with diabetes)−variable can be explained by its (linear relationship/relationship)…arrow_forwardPlease help me answer the following question The drop down for question (e, f, and g) is (YES/NO) Based on the P-value above, the assumption of equal variances among the four machines (Is Met/Is Not Met) Based on the data, the average fill for machine 3 is (statistically lower than/statistically higher than/the same as/not statistically different than/statistically different than/Hard to say then when comparing to/Refuse to say when comparing to) machine 1.arrow_forward
- Business Discussarrow_forward1 for all k, and set o (ii) Let X1, X2, that P(Xkb) = x > 0. Xn be independent random variables with mean 0, suppose = and Var Xk. Then, for 0x) ≤2 exp-tx+121 Στ k=1arrow_forwardLemma 1.1 Suppose that g is a non-negative, non-decreasing function such that E g(X) 0. Then, E g(|X|) P(|X|> x) ≤ g(x)arrow_forward
- Functions and Change: A Modeling Approach to Coll...AlgebraISBN:9781337111348Author:Bruce Crauder, Benny Evans, Alan NoellPublisher:Cengage LearningCollege AlgebraAlgebraISBN:9781305115545Author:James Stewart, Lothar Redlin, Saleem WatsonPublisher:Cengage LearningAlgebra and Trigonometry (MindTap Course List)AlgebraISBN:9781305071742Author:James Stewart, Lothar Redlin, Saleem WatsonPublisher:Cengage Learning
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw HillBig Ideas Math A Bridge To Success Algebra 1: Stu...AlgebraISBN:9781680331141Author:HOUGHTON MIFFLIN HARCOURTPublisher:Houghton Mifflin Harcourt





