Specifying Y-intercept of a fit curve

[Christopher Golden]

I am completing a performance degradation analysis and have used the model wizard to choose the Gompertz model as the "best fit" for my data set. However, the fit curve does not pass through (0,0) as is desired. I would like the curve to reflect zero performance degradation at zero usage. Is there any way to accomplish this result manually in the software by specifying a Y-intercept or otherwise? Thanks,

Chris Golden

[Tarik El-Azzouzi]

The Gompertz model is y=a*b^(c^x)
For x=0, y=a*b^1 which can’t be zero unless a or b are zero for which case, the model would be y=0 for any x value. Therefore for the Gompertz model, the model can’t go through (0,0). Other models, such as the linear, allow (0,0).