Statistics- unbiased estimator #3

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SUMMARY

The discussion focuses on determining the better unbiased estimator for the unknown parameter \Theta from a uniform distribution, given two estimators: \Theta1 = (6/5)*Ymax and \Theta2 = 6*Ymin. It is established that the variances of Ymax and Ymin are equal due to the symmetry of the distribution. Consequently, since \Theta1 has a variance that is 1/25 of \Theta2, \Theta1 is the superior estimator. This conclusion aligns with intuitive reasoning, as a lower variance indicates a more reliable estimator.

PREREQUISITES
  • Understanding of uniform probability density functions (pdf)
  • Knowledge of variance calculation and properties
  • Familiarity with unbiased estimators in statistics
  • Basic concepts of statistical symmetry
NEXT STEPS
  • Study the properties of unbiased estimators in statistical inference
  • Learn about variance and its implications in estimator efficiency
  • Explore the implications of symmetry in probability distributions
  • Investigate the impact of sample size on estimator performance
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Statisticians, data analysts, and students studying statistical estimation methods will benefit from this discussion, particularly those interested in understanding unbiased estimators and their variances in uniform distributions.

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Homework Statement



Suppose that n=5 observations are taken from the uniform pdf, fY=1/\Theta 0<y<\Theta
where \Theta is unknown. Two unbiased estimators for \Theta are

\Theta1= (6/5)*Ymax
\Theta2= (6)*Ymin

which estimator would be better to use? hint: What must be true of Var(Ymax) and Var(Ymin) given that fy is symmetric ? Does your answer as to which estimator is better make sense on intuitive grounds ? Explain.

Homework Equations



Var(Y)=E[Y2] - E[Y]2

Ymin=n*(1-FY(y))n-1fY(y)

Ymax=n*(FY(y))n-1fY(y)

The Attempt at a Solution



I'm trying to calculate the variances of both the estimators and see which one is smaller.
But, there is the extra information like, n=5 and that the distribution is symmetric, and I'm sure I need to use it.
Plus, I don't know how to answer it on intuitive grounds.
Would appreciate any help.
Thanks.

EDIT:

Now, I am still trying to solve it, and if I know that the distribution is symmetric, the variance of Ymin and Ymax are the same.
However, since the first estimator is divided by 5, we know that it's 1/25 of the variance of the second estimator.
Can I say this ? Is this the"on intuitive grounds" answer that they are asking ?
What about the sample size n=5 ? what do I do with it ?

Thanks
 
Last edited:
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anybody ?

can't figure it out :\
 

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