Normal Distribution: Sample Mean & Variance

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SUMMARY

The discussion centers on proving the standardization of the sample mean in a normal distribution using both moment generating functions and cumulative distribution functions. Specifically, it demonstrates that the standardized variable \( z = \frac{\bar{x} - \mu}{\sigma/\sqrt{n}} \) follows a standard normal distribution \( N(0,1) \) when \( \bar{x} \) is derived from a random sample of size \( n \) from a normal distribution \( N(\mu, \sigma^2) \). Participants clarified the distinction between the sample mean and the distribution of \( z \), leading to a successful proof just before the submission deadline.

PREREQUISITES
  • Understanding of normal distribution properties
  • Familiarity with moment generating functions
  • Knowledge of cumulative distribution functions
  • Basic statistical concepts such as sample mean and variance
NEXT STEPS
  • Study the derivation of moment generating functions for normal distributions
  • Learn about the Central Limit Theorem and its implications for sample means
  • Explore the properties of cumulative distribution functions in statistical analysis
  • Investigate applications of the standard normal distribution in hypothesis testing
USEFUL FOR

Statisticians, data analysts, and students studying probability and statistics who seek to deepen their understanding of normal distributions and their applications in inferential statistics.

axe69
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ok guys , i need an answer to this question , use both moment generating function and cummulative function to show that z=(x(bar)-[tex]\mu[/tex])/([tex]\sigma[/tex]/[tex]\sqrt{n}[/tex]) if x(bar) is based on a random sample of size n from a normal([tex]\mu[/tex],[tex]\sigma[/tex]^2)
 
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Sorry this question is rather vague. Do you wish to prove that a normalized normal is a normal (0,1)? The x(bar) is deceiving, as it usually means sample mean, in the case you are taking a sample mean then z is not a distribution.
 
mannaged to prove it ,and jst b4 the submition date ,thnx 4 you help
 

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