Chapter one

Ordinal Level

The ordinal level of measurement presumes that one classification is ranked higher than another.

Two types of statistics

1. Descriptive statistics are procedures used to organize and summarize data. 2. Inferential statistics involve taking a sample from a population and making estimates about a population based on the sample results.

Explain the difference between a discrete and a continuous variable.

A discrete variable may assume only certain values. A continuous variable may assume an infinite number of values within a given range.

Population

A population is an entire set of individuals or objects of interest or the measurements obtained from all individuals or objects of interest.

Explain the difference between a sample and a population.

A population is the entire set of individuals or objects and a sample is a portion of it.

There are two types of variables.

A qualitative variable is non-numeric. Usually we are interested in the number or percent of the observations in each category. Qualitative data are usually summarized in graphs and bar charts.

four levels of measurement.

Nominal Level Ordinal Level Interval Level Ratio Level

Ratio level

The ratio level of measurement has all the characteristics of the interval level, plus there is a 0 point and the ratio of two values is meaningful.

Explain the difference between qualitative and quantitative variables. Give an example of qualitative and quantitative variables.

Qualitative data is not numerical, whereas quantitative data is numerical.

nominal level

With the nominal level, the data are sorted into categories with no particular order to the categories.

Sample

A sample is a part of the population

Statistics

Statistics is the science of collecting, organizing, presenting, analyzing, and interpreting data to assist in making more effective decisions.

Interval Level

The interval level of measurement has the ranking characteristic of the ordinal level of measurement plus the characteristic that the distance between values is a constant size.

Quantitative

There are two types of quantitative variables and they are usually reported numerically. Discrete variables can assume only certain values, and there are usually gaps between values. A continuous variable can assume any value within a specified range.