Skip to main content

Four Types of Measurement

Behavioral scientists commonly refer to four types of measurement or scales. Understanding the types of measurement or scales is important because some numbers have limited applications and they are misused.

The four types of measurement scales are as follows: Nominal, Ordinal, Interval, and Ratio.

This information is taken from Chapter 5 of Applied Statistics: Concepts for Counselors

Nominal Scale

This is often called the naming scale. The numbers allow researchers to classify people as belonging in a group. The numbers cannot be added or ranked.

If we were studying treatment of people with depression we might form two groups simply numbers 1 and 2 for those getting treatment and those on a waiting list for treatment. All people in the study have a number but the number is just a classification.

Numbers on sports team players may represent positions.

Ordinal Scale

The ordinal scale is a ranking scale. Performance can be ranked in order of high to low. You can rate projects, products, and many other human characteristics. Sporting events include rating scales when judging an atheletes performance. For example, you could rate gymnastic performance on a scale from 1 to 10 or even 1 to 100.

Interval Scale

Interval scales are common in the behavioral sciences. Many test scores are interval scores. Scientists argue about the properties of the intervals but for general purposes, these scores are routinely used in education, counseling, psychology, social work, sociology, and other disciplines.

Scores on tests of intelligence, achievement, and personality are often interval scale scores. Test administrators can calculate an arithmetic average (M, Mean) and standard deviation (SD). It is possible to compare how individuals score on a test compared to the average for their group. It is also possible to determine if group averages are different from each other.

Caution is needed with test scores. For example, a person with an IQ of 50 is NOT half as intelligent as someone with an IQ of 100. It is not correct to compare scores on tests measured on an interval scale as if the scores represented a ratio. Again, a standard score of 130 on a reading test does not mean the person is twice as good at reading as a person who score a 65.

Ratio Scale

The ratio scale is like the interval scale but the numbers can have a true zero point and we can meaningful speak about ratios.

A person who weighs 200 pounds is twice as heavy as a person who weighs 100 pounds.

Measures of height and weight are examples of ratio scales.

Read more about statistics and basic projects in
Creating Surveys on AMAZON


My Page

My Books  

 Geoff W. Sutton

TWITTER  @Geoff.W.Sutton

Publications (many free downloads)
  Academia   Geoff W Sutton   (PhD)
  ResearchGate   Geoffrey W Sutton   (PhD)


Popular posts from this blog

Personal Self-Concept Questionnaire (PSQ)

  The Personal Self-Concept Questionnaire  ( PSQ )   Overview The Personal Self-Concept Questionnaire (PSQ) measures self-concept based on ratings of 18 items, which are grouped into four categories: Self-fulfilment, autonomy, honesty, and emotional self-concept. Subscales : The PSQ has four subscales 1. Self-fulfilment (6 items) 2. Autonomy (4 items) 3. Honesty (3 items) 4. Emotional self-concept (5 items)  👉 [ Read more about Self-Concept and Self-Identity] The PSQ is a Likert-type scale with five response options ranging from totally disagree to totally agree. Reliability and Validity In the first study, coefficient alpha = .85 and in study two, alpha = .83. Data analysis supported a four-dimensional model (see the four categories above). Positive correlations with other self-concept measures were statistically significant. Other notes The authors estimated it took about 10 minutes to complete the PSQ. Their first study included people ages 12 to 36 ( n = 506). In the second s

Student Self-Efficacy

  Assessment name:  STUDENT SELF-EFFICACY SCALE * Note. This post has been updated to provide an available measure of student self-efficacy. ———- Scale overview:  The  student self-efficacy scale i s a 10-item measure of self-efficacy. It was developed using data from university nursing students in the United States. Authors: Melodie Rowbotham and Gerdamarie Schmitz Response Type:  A four-choice rating scale as follows: 1 = not at all true 2 = hardly true 3 = moderately true 4 = exactly true   Self-efficacy is the perception that a person can act in a way to achieve a desired goal.  Scale items There are 10 items. Examples: I am confident in my ability to learn, even if I am having a bad day. If I try hard enough, I can obtain the academic goals I desire.   Psychometric properties The authors reported that their sample scores ranged from 25 to 40 with a scale mean of 34.23 ( SD  = 3.80. Internal consistency was high at alpha = .84. The authors reported the results of a principal compon

Mathematics Self-Efficacy and Anxiety Questionnaire (MSEAQ)

  Scale name: Mathematics Self-Efficacy and Anxiety Questionnaire (MSEAQ) Scale overview: The Mathematics Self-Efficacy and Anxiety Questionnaire (MSEAQ) is a 29-item self-report measure of both mathematics self-efficacy and mathematics anxiety. Author: Diana Kathleen May Response Type: Items are rated on a 5-point Likert-type scale following a “no response” option: 1 = Never 2 = Seldom 3 = Sometimes 4 = Often 5 = usually Sample items 1. I feel confident enough to ask questions  in my mathematics class. 6. I worry that I will not be able to get a  good grade in my mathematics course.   Subscales and basic statistics for the MSEAQ       Self-Efficacy M = 44.11, SD = 10.78, alpha = .93       Anxiety M = 46.47, SD = 12.61, alpha = .93       Total Scale M = 90.58, SD = 22.78, alpha = .96 Reliability: See the Cronbach’s alpha levels reported above. Validity: There were significant positive correlations with similar measures. The results of a Fa