Tableau only allows trend lines (scatter plot) with a minimum of 2 factor polynomials. I typically generate single factor polynomials (y = ax^b). am I just out of luck here?
here is my scenario. we generate equations to predict Y. I want to show how new data plots against that equation. I want to display that equation via a trend line. so what I do is add a calculation to my measure that models that equation and then I make a 2 factor polynomial trend line to go through it. then I hide the marks so it looks like a nice curved line. This is technically not accurate as my equation is a single polynomial equation. Most of the time I find this is close but not exact. it also depends a lot on how much "new data" I have to plot against the equation. if I have a lot, it looks nice, but if I only have a few data points the 2 polynomial trend line looks awful.