open housing.gdt --quiet

# define the series we'll need 
logs price lotsize
d2 = bedrooms <= 2
d3 = bedrooms == 3
d4 = bedrooms == 4
d5 = bedrooms >= 5

# two variants of the dummies model
ols l_price 0 l_lotsize bathrms airco d3 d4 d5
ols l_price 0 l_lotsize bathrms airco d2 d4 d5

# replicate Table 3.1
ols l_price 0 l_lotsize bedrooms bathrms airco

# non-nested F tests
print "Artificial nesting model"
ols l_price 0 l_lotsize bathrms airco bedrooms d3 d4 d5
print "test: is the 'bedrooms' model an acceptable restriction?"
omit d3 d4 d5 --quiet
print "test: is the 'dummies' model an acceptable restriction?"
omit bedrooms --quiet