Hi, I'm working in crustacean maturity, using breakpoint analysis. I used total length and Carapace length (linearly related) to find a break point, wich is actually the size at maturity. Both sizes are measured with error, so Modell II aplies. Piecewise regression uses model I to find breakpoints. Do anybody nows a way of finding the break point using a model II regression? Any feedback on this is highly appreciated. Angel Segura Instituto de Investigaciones Pesqueras Facultad de Veterinaria Montevideo-Uruguay