Abstract
A specific function f(r) involving a ratio of complicated gamma functions depending upon a real variable r(> 0) is handled. Details are explained regarding how this function f(r) appeared naturally for our investigation with regard to its behavior when r belongs to R+. We determine explicitly where this function attains its unique minimum. In doing so, quite unexpectedly the customary Cramér-Rao inequality comes into play in order to nail down a valid proof of the required lower bound for f(r) and locating where is that lower bound exactly attained.
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Mukhopadhyay, N., Bishnoi, S.K. An Unusual Application of Cramér-Rao Inequality to Prove the Attainable Lower Bound for a Ratio of Complicated Gamma Functions. Methodol Comput Appl Probab 23, 1507–1517 (2021). https://doi.org/10.1007/s11009-020-09822-w
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DOI: https://doi.org/10.1007/s11009-020-09822-w
Keywords
- Asymptotic distribution
- CLT
- Confidence interval
- Cramér-Rao inequality
- Gamma functions
- Point estimation
- Random CLT
- Stopping time