Levels of measuremen

• Nominal data, often referred to as categorical data, is a frequency count of a particular variable. These are discrete (do not overlap) and have no natural order. Examples of this type of data is taste in music.
• Ordinal data is also categorical data but it has a natural order. The difference between each point in an ordinal scale is not consistent. Examples of this type of data include height among a group of people.
• Interval data are scales which are precise due to have equal intervals / increments between each adjacent point. This data is continuous and the value recorded can be any point on the scale used. Examples of this type of data is time in seconds.
• Ratio data is interval data with an absolute zero point. An example of this is temperature in Kelvin as it cannot go below 0 degrees.