Suppose we are looking at an ordinal variable with $4$ categories. So there are three threshold coefficients $b_1, \dots b_3$ and one probit slope $b_4$. What is the interpretation of the following expressions: $$\frac{b_{1}}{b_{4}^{2}}, \frac{b_{2}}{b_{4}^{2}}, \frac{b_{3}}{b_{4}^2}, \frac{1}{b_{4}}$$
assuming a multivariate normal distribution?