Why attendance was represented with 0 and 1 ?
As I understand, the attendance is nominal categorical variable.
Why have we represented using ordinal measures?
We should have used two dummy variables.
or where am I wrong ?
Thank you for your question!
When working with categorical variables, we need to transform the possible outcomes in a way that is suitable for performing calculations. Therefore, we need to assign each outcome a number. These numbers will inevitably come in order, as numbers are ordinal in nature.
Whenever the categorical variable is binary, it is most convenient to represent the outcomes as 0 and 1. It doesn't matter which number you assign to either of the outcomes. Having used Yes as 0 and No as 1 would've solved the problem equally well. The only thing that would've changed are the coefficients.
Hope this answer helps!