pre-advising 'publish'

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2024-10-04 12:59:37 -04:00
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@@ -84,9 +84,13 @@ There are three probability axioms:
\begin{enumerate}
\item \textbf{Expectation - }The weighted average of the probabilities in the sample space
\[\sum_{}^{S}{P(A) * A} = E \quad\text{where }E\text{ is the expected value}\]
\item \textbf{Variance - }The spread of possible values for a random variable
\item \textbf{Standard Deviation - }something
\[std = \sqrt{V}\quad\text{where variance is }V\]
\item \textbf{Variance - }The spread of possible values for a random variable, calculated as:
\[\sigma^{2}=\frac{\sum(X - \mu)^{2}}{N}\]
Where \(N\) is the population size, \(\mu\) is the population average, and \(X\) is each value in the population.\\
For samples, variance is calculated with \textbf{Bessel's Correction}, which increases the variance to avoid overfitting the sample:
\[s^{2}=\frac{\sum(X - \bar{x})^{2}}{n - 1}\]
\item \textbf{Standard Deviation - }The square root of the variance, giving a measure of the average distance of each data point from the mean in the same units as the data.
\[\sigma = \sqrt{V}\quad\text{where variance is }V\]
\end{enumerate}
\subsubsection{Probability Functions}
@@ -128,11 +132,9 @@ means will approach the true mean of the population.
The Central Limit Theorem states that the sampling distribution of a sample mean is a normal distribution even when the
population distribution is not normal.
\[
\frac{\sqrt{n} \left( \bar{X}_n - \mu \right)}{\sigma} \xrightarrow{d} N(0, 1),
\]
\[
\text{Where \( \bar{X}_n = \frac{1}{n} \sum_{i=1}^{n}\), \( X_i \) is the sample mean, and \( N(0, 1) \) is a standard normal distribution.}
\frac{\sqrt{n} \left( \bar{X}_n - \mu \right)}{\sigma} \xrightarrow{d} N(0, 1)
\]
Where \(X_i\) is the sample mean, \(N(0, 1)\) is a standard normal distribution, and \(\bar{X}_n = \frac{1}{n} \sum_{i=1}^{n}X_i\).\\
This is a challenging to understand solely as an equation. As an example, take a sample of two six-sided dice rolls and average their numbers.
The more sample averages taken, the more they will resemble a normal distribution where the majority of samples average around 3.
@@ -140,6 +142,13 @@ The more sample averages taken, the more they will resemble a normal distributio
Confidence is described using a confidence interval, which is a range of values that the true value is expected to be in, and its associated confidence level,
which is a probability (expressed as a percentage) that the true value is in the confidence interval.
It is important to note that confidence levels, such as 95\%, do not indicate that the real value is within 5\% of the point estimate. The confidence level expresses
the probability that the real value is in the range provided by the confidence interval.
At the highest level, calculating confidence intervals is simply the observed statistic (generally the mean) plus or minus the standard error.
To calculate standard error, kys.
% Confidence intervals can be calculated with z-tests, t-tests. Go into parametric vs non-parametric
\subsubsection{Statistical Inference}