Data Collection/Types of Data

Observational Studies

Passive studies, with goal being to observe conditions of groups in past, present, or future without inferencing generating information. (Ex: the economy)

Experiments

Active studies, with goal to manipulate experimental conditions to study their effect on outcome

Surveys

Designed observational study where data is collected at a particular point in time.

Discrete Data

Data is numerical and the number of values is finite or countable (Ex: counting students in attendance)

Continuous Data

Numerical data that comes from many possible qualitative values, where collection of values is not countable. (Ex: Height, Weight before starting weight-loss program)

Nominal/Categorical Data

Variables consist of names, labels and categories only, data cannot be arranged in some order. (Qualitative)

Ordinal Data

Data that can be-arranged in order but the differences cannot be obtained (Ex; 0-10 on service, course grades)

Interval Data

Variables can be arranged in oder and the differences between are found and are meaningful. Can quantify the difference between them. No true zero.

Ratio Data

Data can be arranged in order and are meaningful, but there is a true zero