1.2: data classification

ordinal level of measurement

- qualitative data - data can be arranged in order (ranked) - precise differences between ranks do not exist - eg: letter grades, movie ratings, survey responses

nominal level of measurement

- qualitative data only - categorized using names, labels, qualities - no order or rank - no mathematical computations can be made - eg: gender, ethnicity, SSN, school ID

ratio level of measurement

- quantitative data - zero entry is an inherent zero (implies none) - there is a starting point to the data - ratio of two data values can be informed - eg: height, weight, BMI, speed

interval level of measurement

- quantitative data - data can be ordered - differences between data entries are meaningful - zero represents a position on a scale - eg: temperature, years, evolution

list the levels of measure

1. nominal 2. ordinal 3. interval 4. ratio

what are the two types of quantitative variables?

continuous and discrete data

continuous data

quantitative data that can take on any value in a given interval and are usually measurements

discrete data

quantitative data that can take on only particular values and are usually counts

quantitative variables

variables that can be counted or measured

qualitative variables

variables that have distinct categories according to some characteristic or attribute