Statistics

Statistics provides tools for collecting, analyzing, and interpreting data to draw meaningful conclusions. This topic covers descriptive statistics (mean, median, standard deviation), regression and correlation, confidence intervals, hypothesis testing, chi-square tests, the normal distribution, and sampling methods.

Statistics drives evidence-based decisions in healthcare (clinical trials), business (A/B testing and market research), public policy (census analysis), and scientific research across every discipline.

Practice Tips

• 1Always start with descriptive statistics and a visual summary (histogram or boxplot) before running any inferential test, so you understand the shape and spread of your data.
• 2For hypothesis testing, state the null and alternative hypotheses clearly, choose the significance level before computing, and interpret the p-value in context.
• 3When building a confidence interval, remember that increasing the sample size narrows the interval, while increasing the confidence level widens it.