Four key concepts are discussed in this unit:
1.Population (总体) is a collection of all possible individuals, objects, or measurements of interest.
- All the students studying business statistics
- All the registered voters in the city
- All the trees on the campus
2. Sample （样本）is a portion, or part, of the population of interest.
- The students who got A in business statistics test
- Women voters registered in the city (parts of all the people…)
- Yong trees on the campus (parts of all the trees … )
3. Parameter （参数）: A summary measure of a population is a parameter
A statistic computed on everyone in the population is called a population parameter.
A property of a population. Greek letter (µ) or capital letter (P, N)
4.Statistic(统计值) – an observable property of a sample.
- Any number calculated from sample data, describes a sample characteristic.
- A statistic computed on everyone in a sample is called a sample statistic