Statistical Inference
Statistical inference is the process of using data from a sample to draw conclusions or make predictions about the larger population from which the sample was drawn. Since studying an entire population is often impractical or impossible, inference provides the formal methods for generalizing from a part to the whole. This branch of statistics primarily involves two approaches: estimation, which uses sample data to determine a likely range of values for a population characteristic (e.g., a confidence interval for the average income), and hypothesis testing, which assesses evidence to make a decision about a specific claim regarding the population (e.g., whether a new drug is effective). Crucially, all statistical inferences are grounded in probability theory, allowing us to quantify the uncertainty inherent in making conclusions based on incomplete data.