Statistics and Inference

Easy

Whether a number you measured means anything: Bessel's correction, standard error, correlation, the t-statistic, and the bootstrap.

Learning Objectives

→Explain why sample variance divides by n-1, and what ddof does
→Tell a standard deviation from a standard error, and build a confidence interval
→Compute correlation from covariance, and name a relationship it cannot see
→Compute a two-sample t-statistic and read it as a signal-to-noise ratio
→Bootstrap a sampling distribution by resampling with replacement

Sample Variance and Bessel's Correction

~10 min· Easy

Standard Error and a Confidence Interval

~12 min· Easy

Covariance and Correlation

~12 min· Easy

The Two-Sample t-Statistic

~14 min· Medium

Bootstrap the Sampling Distribution

~15 min· Medium

Optional multiple-choice questions on the ideas behind this section. Most useful after you have tried the coding problems above.