?DEMO
STAT CONSUME / MEAN=CBAR
STAT INCOME / MEAN=IBAR
OLS CONSUME INCOME PRICE
TEST INCOME=1
* Calculate a standard error for the income elasticity
TEST INCOME*(IBAR/CBAR)
* A joint test
TEST
  TEST INCOME=1
  TEST PRICE=-1
END
* Non-linear hypothesis testing
TEST INCOME*PRICE=-1
TEST
  TEST PRICE=-1
  TEST INCOME*PRICE=-1
END
STOP