# ML Wiki

## Contents

### Points Estimates

An estimate is a point estimate when we use only one certain value to describe what we think about the whole population [1]

### Examples

• $\bar{x}$ - sample mean, $\mu$ - population mean, $\bar{x}$ estimates $\mu$
• $\hat{p}$ - estimate of proportion, $p$ - true proportion
• $s$ - sample Standard Deviation, $\sigma$ - std of population
• etc

Point estimates are not necessarily good, but they tend to become better as we collect more data

### Standard Error

Standard Error - a measure of uncertainty associated with this point estimate

### Confidence Intervals

A point estimate - is a single plausible value for a parameter

• but one point is rarely enough - we'd like to have a range of plausible values
• so we typically use Confidence Intervals