10.)

a.) There is some evidence that political views are shaped by where one grew upin a city, in a suburb, or in a rural area. Using the "comm" variable (0 = rural; 1 = suburban; 2 = urban), we run a regression explaining where one lies along the abortion spectrum (0 = pro-life, 4 = pro-choice). Using the results below, assess that relationship. What is the null hypothesis (be specific)? Do we reject it or not? Interpret your findings for the layperson as well.

. regress abort comm

Source |SSdfMSNumber of obs=305

-------------+----------------------------------F(1, 303)=2.57

Model |5.3696030515.36960305Prob > F=0.1100

Residual |633.3648233032.09031295R-squared=0.0084

-------------+----------------------------------Adj R-squared=0.0051

Total |638.7344263042.10110009Root MSE=1.4458

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abort |Coef.Std. Err.tP>|t|[95% Conf. Interval]

-------------+----------------------------------------------------------------

comm |.1886133.11768111.600.110-.0429625.420189

_cons |2.79301.138260420.200.0002.5209383.065082

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b.) Our "comm" variable is nice and ordinal, but it's not really a ratio level variable and thus really shouldn't be used in a regression format in such as manner. Instead, we decide to use a dummy variable approach. The variables "urban," "rural," and "suburban" are each dichotomous variables that indicate whether the respondent is either in or not in those respective categories. We decide to use suburban (50%) as the reference category. In considering the following results, what more have we learned about the relationship between locale and support for abortion? Explain what our dummy variable approach tells us. Interpret the findings in terms of the null hypotheses and for the layperson.

. regress abort rural urban

Source |SSdfMSNumber of obs=305

-------------+----------------------------------F(2, 302)=2.18

Model |9.1027415224.55137076Prob > F=0.1145

Residual |629.6316853022.08487313R-squared=0.0143

-------------+----------------------------------Adj R-squared=0.0077

Total |638.7344263042.10110009Root MSE=1.4439

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abort |Coef.Std. Err.tP>|t|[95% Conf. Interval]

-------------+----------------------------------------------------------------

rural |-.3973856.1953319-2.030.043-.7817695-.0130017

urban |-.0467271.2115281-0.220.825-.4629827.3695284

_cons |3.091503.116733126.480.0002.861793.321217

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c.) We run one last regression on abortion politics, including only the dummy variable for rural locale. What is our reference group in this case? Explain the results. Given the three relationships we've explored here in these three regressions, what do think is going on here? What's the best way to express the statistical relationship between support for abortion rights and where one grew up?

. regress abort rural

Source |SSdfMSNumber of obs=305

-------------+----------------------------------F(1, 303)=4.33

Model |9.0010037719.00100377Prob > F=0.0383

Residual |629.7334223032.07832813R-squared=0.0141

-------------+----------------------------------Adj R-squared=0.0108

Total |638.7344263042.10110009Root MSE=1.4416

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abort |Coef.Std. Err.tP>|t|[95% Conf. Interval]

-------------+----------------------------------------------------------------

rural |-.3831551.1841137-2.080.038-.7454585-.0208516

_cons |3.077273.097195431.660.0002.8860093.268536

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