Discussion

The acronym NOIR is used to remember the four scales of measurement. The four scales of measurement include, nominal, ordinal, interval, and ratio. During this unit, we also discussed to two methods of assessing or evaluating scores; these include norm- referenced Testing and criterion- referenced testing.

Norminal scales involve categorizing characteristics. According to out text, Psychological Testing and Assessment, "these scales involve classifications bases on one or more distinguishing characteristics, where all thing must be placed into mutually exclusive categories" ( Cohen, Swerdlik, Sturman, 2013).

For example, the color of someones hair (1. Blonde, 2. Brown, 3. Red..) Norminal scales can impact norm-referenced testing by categorizing test scores of individuals by age of students. Since the items in norm- referenced testing varies in difficulty, we can look at the age of students to understand the learning capabilities within each age or age range.

Ordinal scales also involves classification, however, it is classified by ranks (Cohen, Swerdlik, Sturman, 2013). This can also have an impact of norm-referenced testing because it is similar to norminal scales with the use of classifications. For example, class rankings in school, who is at the top 10% of the class vs who is in the top 90% of the class. With interval scales, "we have reached a level of measurement at which it is possible to average a set of measurements and obtain a meaningful result" (Cohen, Swerdlik, Sturman, 2013).

For example, there was a test that we take in elementary school, I can't remember the name of it but it is a test that is on an interval scale. It shows if you are below, at, or above average on each subject. Lastly, with ratio scales, it has a true zero point and it used to measure scores of neurological functioning.

Additionally, speed and reaction time are included with ratio scales" (Cohen, Swerdlik, Sturman, 2013). For example, how long it takes the car to drive 80 miles, if the car was going 50MPH. Both interval and ratio scales can impact criterion- referenced testing based on what you are testing and how it is worded.

Reference:

Cohen, R. J., Swerdlik, M., &Sturman, E. (2013). A Statistic Refresher. In Psychological Testing and Assessment (8th ed., pp. 78-116). New York, NY: McGraw- Hill Companies. doi:978-0-07-803530-2