By Kishi
2025-03-16
By Kishi
The sample mean (\(\bar{x}\)) is an estimator of population mean (\(\mu\)):
\[ \bar{x} = \frac{1}{n} \sum_{i=1}^{n} x_i \] - \(\bar{x}\) is the sample mean - \(n\) is the sample size - \(x_i\) is the sample observations
The sample variance (\(s^2\)) is an estimator of the population variance (\(\sigma^2\)):
\[ s^2 = \frac{1}{n-1} \sum_{i=1}^{n} (x_i - \bar{x})^2 \] - \(s^2\) is the sample variance - \(\bar{x}\) is the sample mean - \(x_i\) is the sample observations
In this example we will take a sample of 10 students heights in in and through this we will estimate the average height of all students
## [1] 66.2
-Bias is the difference between the expected value of the estimator and the value of the parameter that’s estimated
-Consistency: This showcases how close the point estimator stays to the value of the parameter as size increases
-Efficiency: The most efficient point estimator will be the one with the smallest variance
## Warning in geom_histogram(bindwidth = 0.5, color = "blue", fill = "white"): ## Ignoring unknown parameters: `bindwidth`
## `stat_bin()` using `bins = 30`. Pick better value with `binwidth`.