Question

A sample consists of 1,388 observations, where the unit of observation is an individual. packsi is the number of packs of cigarettes woman i smoked per day while pregnant, and bwghti is the birth weight (in ounces) of the woman’s child. Given the information found in the attached STATA output,

(1) The population model implied by the regression output is

(2) In the space below, provide a variable that could possibly affect your dependent variable, but was not accounted for in the simple linear regression model (i.e. is in the u term). Make sure to clearly define your variable and briefly explain why you believe it affects your dependent variable.

Saturday January 19 13:20:33 2019 Page 1 Statistics/Data Analysl 10.1 Copyright 1984-2009 Statistics/Data Analyais StataCorp 905 Lakevay Drive College Station, Texas 77845 USA 00-STATA PC 979-696-4600 79-696-4601 (fax) Special Edition htt stata stata.com www.stata.com Single-user Stata for Windovs perpetual 1icense Serial number: Licensed to: Pierre Brochu University of Ottava Notes 1. (/m# option or -set memory-) 10.00 MB allocated to data (/v# option or -set maxvar-) 5000 maximum variables 1useC:Data Hooldridge BHGHT.DTA, cleaz 2 keep packs bught 3 gen 1packs-1n (packs) (1176 missing values generated) 4gen 1bwght-1nf bught) sreg lbwght packs Source dt Number of obe1388 P 1. 1386)27.98 Prob F R-squared Adj R-squared- 0.0191 Root MSE MS Model Residual 1997781141 9.42255251386 035658407 997781141 0.0000 0.0198 Total50.4203336 1387 036352079 .18883 1bwght Coef. Std.Err. P키티 [95% Conf. Interval] packs08981310169786 .29 .00012311970565065 .779937 cons .7694040053694 888.26 0.000 -758871

Answer 1

1.The population model from the given data would be bwght = β1 + β2 * packs + u where birthweight is the dependent variable and packs is independent variable, u is the error term. From the table above we can interpret β1 to be 4.769404 and β2=-0.898131. The t value is significant, thus when cigarette consumption is increasing by 1 unit Weight of the infant will decrease by -0898131 units.

2. Another factor that could possibly affect the Dependent Variable(bwght), is the diet the pregnant lady is having, it would directly have an impact on the baby's weight. Thus is will possibly a part of u.