Dear All,
Consider a CLASS variable, GENDER, with values F and M. I understand that in SAS, by default, these values are arranged in ascending alphanumeric order which results in M being the last level, and therefore the reference level. Suppose alternatively that we want to set F as the reference level.
Below, I list the coefficients for each case.
I understand that the 2 cases are "equivalent".
However, since in each case the estimated equations are not the same:
y=20.1903-1.6454Gender-0.2917Height
y=18.5448+1.6454Gender-0.2917Height
they provide different probabilities, if they will be manually applied for a new observation.
I apologise in advance for the naive question.
A.
This is not PROC REG. It is (perhaps) the Regression function in SAS Studio.
The models are identical. But you have written them wrong.
y=20.1903-1.6454*(Gender='F')-0.2917*Height
y=18.5448+1.6454*(Gender='M')-0.2917*Height
For females, the first model equates to y = 20.1903-1.6454-0.2917*Height = 18.5449 - 0.2917*Height
For females, the second model equates to y = 18.5448 - 0.2917*Height
These are identical (except for roundoff error).
This cannot be the output from PROC REG. What PROC are you actually using? Show us the code used.
This is not PROC REG. It is (perhaps) the Regression function in SAS Studio.
The models are identical. But you have written them wrong.
y=20.1903-1.6454*(Gender='F')-0.2917*Height
y=18.5448+1.6454*(Gender='M')-0.2917*Height
For females, the first model equates to y = 20.1903-1.6454-0.2917*Height = 18.5449 - 0.2917*Height
For females, the second model equates to y = 18.5448 - 0.2917*Height
These are identical (except for roundoff error).
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