So this right here, we could write that q is a chi-squared distributed random variable, or that we could use this notation right here. q is, we could write it like this. So this isn't an X anymore, this is the Greek letter chi, although it looks a lot like a curvy X. So it's a member of chi-squared, and since we're only taking one sum over here, we're only taking the sum of one independent, standard normally distributed variable, we say that this only has one degree of freedom. And we write that over here. So this right here is our degree of freedom. We have one degree of freedom right over there.