logit regression function


New Member
I need to plot S-curve for the variables age and score (in precentage)' As they did in an article.
They did an arsin transformation, so first I did it by : 2 * ARSIN(SQRT(var2/100))
And then, they did logit regression And made the plot by it.
The function look like: 100*(SIN(2.667*EXP(-0.976+0.194*Agemon))/(2*(1+EXP(-0.976+0.194*Agemon))))**2
What I ask to know:
1. To get the regression equation, do I need to do regular linear regression of age with that transformed, to get the coefficients a,b for the transformation?
2. What is the number 2.667 in the equation stand for? how I need to calculate it?
3. What is the best way to get the S plot of the Age with that function?