xi: regress write i.prog
Source | SS df MS Number of obs = 200
-------------+------------------------------ F( 2, 197) = 21.27
Model | 3175.69786 2 1587.84893 Prob > F = 0.0000
Residual | 14703.1771 197 74.635417 R-squared = 0.1776
-------------+------------------------------ Adj R-squared = 0.1693
Total | 17878.875 199 89.843593 Root MSE = 8.6392
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write | Coef. Std. Err. t P>|t| [95% Conf. Interval]
-------------+----------------------------------------------------------------
_Iprog_2 | 4.92381 1.539279 3.20 0.002 1.888231 7.959388
_Iprog_3 | -4.573333 1.775183 -2.58 0.011 -8.074134 -1.072533
_cons | 51.33333 1.287853 39.86 0.000 48.79359 53.87308
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a) Interpret the value of the constant (_cons).
b) Interpret the value _Iprog_2.
2) Consider the following regression results
regress math read write
Source | SS df MS Number of obs = 200
-------------+------------------------------ F( 2, 197) = 104.72
Model | 9000.27927 2 4500.13963 Prob > F = 0.0000
Residual | 8465.51573 197 42.9721611 R-squared = 0.5153
-------------+------------------------------ Adj R-squared = 0.5104
Total | 17465.795 199 87.7678141 Root MSE = 6.5553
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math | Coef. Std. Err. t P>|t| [95% Conf. Interval]
-------------+----------------------------------------------------------------
read | .4 .0564838 7.38 0.000 .3055581 .5283391
write | .3 .0610982 5.58 0.000 .2206314 .4616124
_cons | 12.8 2.82162 4.56 0.000 7.30061 18.42952
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a) Write the regression prediction equation for math'.
b) What is the predicted math score for a student with a read score of 40 and
a write score of 40?