<div dir="ltr"><div class="gmail_default" style="font-family:trebuchet ms,sans-serif">Delcio,<br><br></div><div class="gmail_default" style="font-family:trebuchet ms,sans-serif">Basta fazer assim:<br><br><span style="font-family:monospace,monospace">durner <- as.formula(theta ~<br>                         <span style="color:rgb(255,0,0)">w0</span> * (thetar + ((thetas - thetar)/(1 + (alpha0 * psi)^n0)^(1 - 1/n0))) +<br>                         <span style="color:rgb(255,0,0)">(1 - w0)</span> * (thetar + ((thetas - thetar)/(1 + (alpha1 * psi)^n1)^(1 - 1/n1))))<br><br>dur <- nlsLM(durner,<br>             start = list(<span style="color:rgb(255,0,0)">w0 = 0.6</span>,<br>                          thetas = 0.5,<br>                          thetar = 0.25,<br>                          alpha0 = 0.1,<br>                          n0 = 2,<br>                          alpha1 = 0.1,<br>                          n1 = 1),<br>             data = dados,<br>             algorithm = "LM",<br>             trace = "F",<br>             control = list(maxiter = 500))<br>summary(dur)</span><br><br>À disposição.<br></div><div class="gmail_default" style="font-family:trebuchet ms,sans-serif">Walmes.<br></div><div class="gmail_default" style="font-family:trebuchet ms,sans-serif"><br></div>​</div>