Measurement and Assessment of Research Results

1. Measurement and Assessment of Research Results

2. Four Levels or Scales of Measurement • Nominal • Ordinal • Interval • Ratio

3. Four Levels or Scales of Measurement • Nominal – A, B, C, or 1, 2, 3 • EX: 1 = boys, 2 = girls; • 1 = in sports, 2 = not in sports; • 1 = reduced lunch, 2 = not reduced lunch • 1 = freshmen, 2 = sophomores, 3 = juniors, 4 = seniors • 1 = American, 2 = Canadian, 3 = Mexican • 1 = experimental group, 2 = control group

4. Four Levels or Scales of Measurement • Ordinal– Rank from first to last, best to worst. Items are ranked, but the distance between them is unknown and variable. • EX: 1st in class, 2nd in class, 3rd in class • 1st place in race, 2nd place, 3rd place • No. #1 song, #2 song, #3 song • Valedictorian, Salutatorian

5. Four Levels or Scales of Measurement • Interval– Rank with equal intervals or distance between numbers; lacks an absolute-zero point • EX: A students, B students, C students, D students • Fahrenheit, Celsius, IQ,

6. Four Levels or Scales of Measurement • Ratio– Has all the properties of nominal, ordinal, interval scales plus an absolute-zero point • EX: A test where someone could miss all answers (number of right answers could equal zero) • Annual income, height, weight, response time

7. Other terms • Testing and assessment • Testing – measuring variables with a device • Assessment – gathering and integrating data – tests, interviews, observations – to make an evaluation • Traits and States • Traits – long-term characteristics • Free-floating anxiety • States – short-term characteristics • Situational anxiety

8. Identifying a good test or assessment procedure - Reliability and Validity • Reliability – if the student takes the same test multiple times, does he get nearly identical scores • Test + retest has pollutants. Familiarity with the test if the time is too short, growth of the individual if the time is too long

9. Identifying a good test or assessment procedure - Reliability and Validity • Split-Half Reliability – split the test in two • Ex: odd questions vs even questions, first 25 questions vs next 25 questions

10. Identifying a good test or assessment procedure - Reliability and Validity • Validity – Does the test support the actions we take based on the scores • Does it test for the traits we were researching? • Gathering evidence supporting the score inference • EX: IQ of 130 assures success in college; if many show IQ of 130, but fail college, test may lack validity • EX: High scores on algebra aptitude test imply success in algebra class; use validity coefficient or expectancy data to determine. Kids fail algebra, problem with test

11. Achievement vs Aptitude tests • Achievement tests measure degree of learning after a person has been exposed to a specific learning experience • Aptitude tests measure broader learning based on information acquired through a lifetime of learning

12. Additional examples of Expectancy Data = Aptitude Tests • SAT for college bound imply they will succeed • CSAT for teachers imply they will succeed • LSAT for law students imply they will succeed • MCAT for medical students imply they wil succeed