# Values of $\alpha$, $\beta$ and $\gamma$ in ets in forecast package

I am using the forecast package in R. I wanted to know how the ets() function finds the value of $\alpha$, $\beta$ and $\gamma$?

Is it by minimizing the SSE or some other criteria?

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The question is clearly answered by the help for the function - ?ets –  Glen_b Nov 21 '12 at 0:17