1 Distinguish between the following statistical concepts aPo

1. Distinguish between the following statistical concepts:

a)Population and sample

b)Parameter and statistic (give examples)

c)The significance level and the power of the test

Solution

Population is the group of individuals under study is also called as universe. The population may be finite or infinite. Whereas sample is a finite subset of statistical individuals in a population . The statistical constants of the population i.e., mean(), variance(²) etc are usually referred to as parameters, whereas statistical measures computed from the sample observations alone i.e., mean(xbar), variance(s²) etc are usually termed as statistics. The significance level is the size of the type1 error(i.e., reject null hypothesis when it is true). Whereas The probability of not committing a Type II error(i.e., accept null hypothesis when it is wrong) is called the power of a hypothesis test.