Finding Moments of Normal Distribution with Unknown Constant

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SUMMARY

The discussion focuses on calculating the first four moments of independent and identically distributed (i.i.d.) random variables X1,...,Xn that follow a Normal distribution with parameters \Theta and c^2*\Theta^2, where "c" is a known positive constant. The user correctly identifies the probability density function (pdf) of the normal distribution and attempts to derive the expected values by substituting (c*\Theta)^2 as the standard deviation. The inquiry centers on whether this approach is valid and how the presence of (c*\Theta)^2 affects the integration of the expectation compared to the standard Normal distribution N(\mu,\sigma).

PREREQUISITES
  • Understanding of Normal distribution properties and pdf
  • Knowledge of moments in probability theory
  • Familiarity with integration techniques for expected values
  • Concept of independent and identically distributed (i.i.d.) random variables
NEXT STEPS
  • Study the derivation of moments for Normal distributions with non-standard parameters
  • Learn about the properties of expected values in relation to transformations of random variables
  • Explore the implications of relative variability in statistical analysis
  • Investigate advanced topics in statistical inference involving unknown parameters
USEFUL FOR

Students and professionals in statistics, data science, and quantitative research who are working with Normal distributions and require a deeper understanding of moment calculations and their applications in statistical modeling.

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Homework Statement


You have i.i.d. random variables X1,...,Xn ~ Normal (\Theta,c^2*\Theta^2), where "c" is a known positive constant (relative variability = std. dev(X)/E[X]) and \Theta is an unknown positive constant. Find the first four moments. E.g E[Xj] where j=1,2,3,4.

Homework Equations

The Attempt at a Solution


So i know the pdf of a normal distribution to be, and what i did was input (c*\Theta)2 as the standard deviation into this. Then I took the expected value of that to get the first order moment. Is this the proper way to do it? Does having (c\Theta)2 change how you integrate the expectation of a normal distribution relative to how you would for the usual N(\mu,\sigma) case?
 
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Homework Statement


You have i.i.d. random variables X1,...,Xn ~ Normal (\Theta,c^2*\Theta^2), where "c" is a known positive constant (relative variability = std. dev(X)/E[X]) and \Theta is an unknown positive constant. Find the first four moments. E.g E[Xj] where j=1,2,3,4.


Homework Equations




The Attempt at a Solution


So i know the pdf of a normal distribution to be, and what i did was input (c*\Theta)^2 as the standard deviation into this. Then I took the expected value of that to get the first order moment. Is this the proper way to do it? Does having (c\Theta)^2 change how you integrate the expectation of a normal distribution relative to how you would for the usual N(\mu,\sigma) case?
 
Sorry the first one i formatted poorly, and couldn't figure it out. New to this forum, just figuring stuff out.
 

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