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Cut Points. ITE - 695. Section One. What are Cut Points?. I. Introduction. A . The more critical the issue (task) the more critical the cut point (example: programming a machine). 1. Interpretation of readouts. 2. Tolerances in measurement. B . Assumption: Test has both of these:
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Cut Points ITE - 695
Section One • What are Cut Points?
I. Introduction A. The more critical the issue (task) the more critical the cut point (example: programming a machine). 1. Interpretation of readouts. 2. Tolerances in measurement. B. Assumption: Test has both of these: 1. Validity. 2. Reliability. C. Select instrument that best measures action needed (performance vs. explanation).
II Types A. Normative-Referenced Testing (NTR) 1. Significance - Accepted reliability & validity 2. Measurement a. Common Averages: - mode - median - mean
II Types (cont.) b. Variability: - range - quartile deviation - standard deviation 3. Reliability - Historical acceptance
II Types (cont.) B. Criterion-Referenced testing (CRT) 1. Significance a. Testing b. Distribution 2. Measurement a. Judgements b. Variables
II Types (cont.) 3. Reliability a. Criterion not based on normal distribution. b. Data dichotomous, mastery/non-mastery.
NORM REFRENCED TESTING 1. Separate test takers 2. Seek Normal Distribution Curve
NORM REFRENCED TESTING 1. Test items separate test - takers from one another. 2. Normal Distribution Curve.
MEASURES of CENTRAL TENDENCIES • MODE • MEDIAN • MEAN • MEASURES of VARIBILITY or SCATTER • RANGE • DEVIATION (QUARTILE) • DEVIATION (STANDARD)
CRITERION REFERENCED TESTING 1. Test items based on specific objectives. 2. Mastery Curve
Standard normal curve with standard deviations SEE HANDOUT
CRITERION REFRENCED TEST 1. Test Compares to Objectives 2. Mastery Distribution
Norm-Reference Testing Criterion Referenced Testing GOALS Test Achievement Test Performance Mastery RELIABILITY Usually High Usually Unknown VALIDITY Usually High Instruction Dependent ADMINISTRATION Variable Standard STANDARD Averages-Based Performance Levels Based MOTIVATION Likelihood of Success Avoidance of Failure COMPETITION Student to Criterion Student to Student INSTRUCTIONAL DOMAIN Cognitive or Psychomotor Low Level Cognitive
Comparison models? INPUT PRODUCT (NRT Results) (Instruction) Model For NRT Construction DESIGN TEST INPUT PRODUCT (Instruction) (CRT Results) MODIFY? YES NO (Test, Objectives, or Instruction) Model For CRT Construction
Mastery curve SEE HANDOUT
Frequency distributions with standard deviations of various sizes SEE HANDOUT
Section II Establishing Cut Points Three Primary Procedures
ESTABLISHING CUT-POINT 1. Informed Judgement 2. Conjectural Approach 3. Contrast Group
I. Informed Judgement A. Significance: Separates mastery from non- mastery B. Procedure: 1. Analyze consequences of mid- classification (political, legal, or operational). 2. Gather previous test-taker data. 3. Ask other stakeholders. 4. Make decision.
II Conjecture Method A. Significance: “Angoff-Nedeisky Method” - most useful. B. Procedure: 1. Select three informed judges. 2. Estimate probability of correct response. 3. Chosen cut-off is average of the three judges.
III Contrast Group Method A. Significance: Single strongest technique; should still use human judgement. B. Procedure: 1. Select judges to identify mastery/non-mastery. 2. Select equal groups (15 minimum, 30 optimum). 3. Administer mastery/non-mastery test to both groups. 4. Plot scores on distribution chart. 5. Make critical cut-off where two distributions intersect. 6. Adjust score between highest non-master and lowest master. score.
Establishing A Criterion Cut-Point Mastery Level - (Separates master from non-master) 1. Informed judgement 2. Conceptual Approach 3. Control groups
Establishing A Criterion Cut-Point (cont.) Mastery Level - (Separates master from non master) 1. Informed judgement 2. Conceptual Approach 3. Control groups
Establishing A Criterion Cut-Point (cont.) Mastery Level - (Separates master from non master) 1. Informed judgement 2. Conceptual Approach 3. Control groups
Contrasting group method of cut-off score selection chart. SEE HANDOUT
Section Three: Reliability
I. Types A. Internal Consistency 1. Kuder-Richardson Method. 2. Computer Statistical Package. 3. Problem: Lack of variance. 4. Problem: Excludes items that measure unrelated objectives. B. Test-Retest Score Consistency.
Review Types of Validity: Methods of Establishing Cut-Points 1. Content 1. Informed Judgment 2. Construct 2. Conjecture Method 3. Criterion-related 3. Contrast Group Method Types of Reliability: 1. Test-Retest 2. Internal Consistency 3. Equivalent forms 4. Interrupter reliability
Section Four: Review Questions • Validity cannot exist without reliability. (True or False) • Since CRT relies on judgment rather than normal distribution for scoring, how is reliability assured? • If it becomes necessary for you to establish cut-point for your training program, which of the three methods would you use and why? (Informed judgment, Conjecture method, or Contrast group method)
Norm-Reference Testing Criterion Referenced Testing GOALS Test Achievement Test Performance Mastery RELIABILITY Usually High Usually Unknown VALIDITY Usually High Instruction Dependent ADMINISTRATION Variable Standard STANDARD Averages-Based Performance Levels Based MOTIVATION Likelihood of Success Avoidance of Failure COMPETITION Student to Criterion Student to Student INSTRUCTIONAL DOMAIN Cognitive or Psychomotor Low Level Cognitive