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Let X1,X2,...,Xn be i.i.d. Gamma random variables with parameters α and λ. The likelihood function is...

Let X1,X2,...,Xn be i.i.d. Gamma random variables with parameters α and λ. The likelihood function is difficult to differentiate because of the gamma function. Rather than finding the maximum likelihood estimators, what are the method of moments estimators of both parameters α and λ?

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