N4 Hosmer and Lemeshow cited a studyconducted at Baystate Medical Center inSpringfield, Massachusetts, to identifyfactors that affect the risk of giving birth toa low-birth-weight baby. Low birth weightis defined as weighing fewer than 2,500grams (5 pounds 8 ounces) at birth. Low-birth-weight babies have an increased riskof health problems, disability, and death.Data were collected on 189 women, 59 ofwhom had low-birth-weight babies and130 of whom had normal-birth-weightbabies. [Hosmer, D. W., & Lemeshow, S.(2000). Applied Logistic Regression, 2nd ed.Hoboken: Wiley. 25]Suppose you use a subsample of thesedata to estimate a least-squares regressionline predicting the baby's birth weight (ingrams) from the mom's age and the mom'sprepregnancy weight (in pounds). In thesubsample, the mean birth weight is 2884grams, with a standard deviation of 32.13;the mean of the mom's age is 27.14 years,with a standard deviation of 5.37; and themean of mom's prepregnancy weight is149.86 pounds, with a standard deviation of31.36. The zero-order (Pearson) correlationbetween the baby's birth weight and themom's age is -0.60, between the baby'sbirth weight and the mom's prepregnancyweight is 0.32, and between the mom's ageand the mom's prepregnancy weight is0.74.You will use the given values to computethe partial slopes of the regressionequation. Before you begin, complete thefollowing table using the values provided.Call the mom's age X1 and the mom'sprepregnancy weight X2.RelevantInformationNeeded forComputingPartial Slopesfor a Multiple RegressionEquationBaby's BirthWeight(grams) Age(years) PrepregnancMom'sMom'sWeight(pouncY = 2,884.00X1 =X2 = 149.8627.14sy = 32.13s1 = 5.37s2 = 31.36Zero-Order Correlationsrylryl = -0.60ry2ry2 = -0.32r12r12 = 0.74Compute the partial slopes and theintercept for the regression equation topredict the baby's birth weight (Y) from themom's age (X1X1) and the mom'sprepregnancy weight (X2X2). Using yourcalculations, complete the followingestimated regression equation:(Equation A) Y = __-_ + ( ) X1 + ( ) X2This equation suggests that among momsof the sameforeveryprepregnancy weight, the baby's predictedbirth weightincrease in the mom'sby -----Using this equation, you would predict thata baby's birth weight born from a momwho is 31 years old and has a prepregnancyweight of 142 pounds will beSuppose your estimated regressionequation is: (Equation B) Y=(2,931.67)+(-0,77)(X1)+(0.16)(X2).Equation B suggests that among moms ofthe same___---, for everyincrease in the mom's prepregnancyweight, the baby's predicted birth weightby__.Using Equation B, you would predict that ababy's birth weight born from a mom whois 31 years old and has a prepregnancyweight of 142 pounds will be

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Accepted Answer

applying regression on above data:
b1 =4.5234 ; b2=0.5657

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