I would like to know the general effort estimation for Automation project. How to do that? What are all the parameter we should consider while autoamtion? Do we have any formula for that? I have little knowledge in that. I would like to know more indepth.
Automation projects are similar to other development projects, if you have an estimation method for estimating software development effort and durations, you should be able to use that same model to obtain a decent estimation for an automation project.
It is all highly dependent on the characteristics of the project and the types of tests you are automating. There are many other factors that have to be considered. The level of expertise and experience of the people doing the work, the actual amount of testing that will be automated, the maturity of the manual test procedures you're automating, the availability of subject matter experts or amount of domain knowledge of the automation team...the list goes on and on.
There is no "silver bullet" formula where you can put a couple of numbers into a calculation and crank out an effort estimate. This issue is tied more to basic project management than to automation specifically. The best estimation method is experience on a similar type project. If you've never done one before, your estimates are pretty much just best guesses.
Hope that helps a little, but I doubt that is the answer you were seeking.