| A | B |
|---|
| nominal level | mutually exclusive, exhausting categories in which no order or ranking can be imposed, qualitative; example, teachers-english, math, science |
| ordinal level | classifies data into categories that can be ranked; precise differences between the ranks do not exist |
| interval level | ranks data and precise differences between units of measure do exist; however, there is no meaningful zero. |
| ratio level | possesses all the characteristics of interval measurement and there exists a true zero; true ratios exist when the same variable is measured on two different members of the population. |
| data set | a collection of data values form |
| data value or datum | each value in the data set |
| statistics sometimes divided into two main areas | descriptive statistics and inferential statistics |
| inferential statistics uses | probability |
| an area of inferential statistics | hypothesis testing, a decision-making process for evaluating claims about a population, based on information obtained from samples |
| variables can be classified as | qualitative or quantitative variables. |
| Grade, judging, rating scale, ranking of tennis players | ordinal level data |
| zip code, gender, eye color, political affiliation, religious affiliation, major field, nationality | nominal level data |
| IQ, temperature | interval level data |
| height, weight, salary, age | ratio level data |
| four commonly used measures that are loosely called averages | men, median, mode, and midrange |
