Homework Will Never End

Chapter 2 – Data Collection Symbols:   ∑ = sum   Population - All of the items we are interested in. (Can be finite, such as passengers on a plane or infinite, such as all Cokes bottled in an ongoing process.)  Population symbols are commonly Greek letters. (But not always)   N = size µ = mean σ 2 = variance σ = standard deviation Sample - A subset of the population that we will actually be analyzing. Sample symbols are commonly Roman letters. (But not always) n = size x̄  = mean s 2 = variance s = standard deviation Definitions: Subject - single member of a data collection we want to study, such as persons,      firms or regions   Variable - a characteristic of a the subject, such as an employee's income or an       invoice amount Versions of Data: Univariate - a data set that consists of one variable (Ex. Income) Bivariate - a data set that consists of two variables (Ex. Income, Age) Multivariate - a data set that consists