The **Central Limit Theorem (CLT)** is a fundamental concept in statistics that explains the behavior of sample means when drawn from any population. It states that, regardless of the population's original distribution, the sampling distribution of the sample mean approaches a normal distribution as the sample size increases, provided the samples are independent and identically distributed.
### Key Points:
1. **Applicability**: CLT applies to large sample sizes (typically \(n > 30\)), even if the population is skewed or non-normal.
2. **Mean and Variance**: The sampling distribution will have the same mean (\(\mu\)) as the population and a reduced standard deviation (\(\sigma/\sqrt{n}\)), called the standard error.
3. **Practical Uses**: CLT is foundational in hypothesis testing, confidence interval estimation, and many statistical methods.
### Example:
Suppose the heights of individuals in a population are not normally distributed. If you repeatedly take random samples and calculate their means, the distribution of these means will resemble a normal distribution as sample size grows.
### Importance:
The CLT simplifies analysis by enabling the use of normal probability models for inferential statistics, making it a cornerstone of modern data analysis.
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