Populations & samples
Japanese school year: Junior high 3
What you learn
You will learn the difference between censuses and sample surveys, as well as the concept of random sampling. This approach is widely used in opinion polls and quality control where surveying the whole population is impractical. Prior knowledge of organizing basic statistical data will support your learning.
Key points
These terms define the groups involved in statistical studies. The entire group of interest is called the "population," while the smaller subset selected for actual study is the "sample."
These terms describe two survey approaches. Investigating every single member of a population is a "census," whereas examining only a selected sample to infer overall trends is a "sample survey."
This is a method used to select an unbiased sample (random sampling). Like a lottery draw, every member of the population has an equal chance of being chosen.
Choose a set to practice.