Measurement Scales (BSAN)

nominal scale

classifies data into distinct categories in which no ranking is implied

ordinal scale

classifies data into distinct categories in which rankings is implied

interval scale

is an ordered scale in which the difference between measurements is a meaningful quantity, but the measurements don’t have a true zero point

ratio scale

is an ordered scale in which the difference between measurements is a meaningful quantity and the measurements do have a true zero point

Interval Ex

Temperature & ACT Testing

Ratio Ex

Height & Age

Population

contains all of the items or individuals of interest that you seek to study

Population Ex

I want to study all BSAN 205 students and I survey all of you

Sample

contains only a portion of a population of interest

Sample Ex

I want to study all BSAN 205 students, but I only survey 4 of you.

Why should we collect data via sampling?

-less time consuming

-less costly

Population Paramater

summarizes the value of a specific variable for a population

Population Parameter Ex

Average age of all BSAN 205 students

Sample Statistic

summarizes the value of a specific variable for sample data

Sample Statistic Ex

average age of 4 BSAN students