Presentation on theme: "Now that you know what assessment is, you know that it begins with a test. Ch 4."— Presentation transcript:
Now that you know what assessment is, you know that it begins with a test. Ch 4
How can you make sure your test is trustworthy? Will it’s measurement be true? If not, what does that say about your evaluation and thus your assessment? Questions to ask yourself:
Your Test Must Have Sensitivity Reliability Objectivity Validity To Be a Good Test
Sensitivity The ability to detect a true difference.
Sensitivity A measurement device or tool….. –Used to apply a number or value - scale –Indicates and separates differences – scale –You can only be sure of your measurement when it fits the scale –Potential for error is high when sensitivity is poor. –Examples
What Happens When Sensitivity is Poor? Too High? –Detect everything –Unable to discriminate between what you’re searching for and everything else you find –Example: Signal vs. signal To Low? –Can’t detect enough –Unable to discriminate between what you’re looking for and nothing –Example: Signal vs. noise or signal vs. silence
Either case, the result is an incorrect result. Incorrect result leads to incorrect judgment. Incorrect judgment leads to incorrect intervention.
Sensitivity True False Measurement Result True State False Positive True Negative False Negative True Positive
Reliability Reliability refers to the consistency of a test –A test given on one day should yield the same results on the next day
Selecting a Criterion Score Mean Score vs. Best Score –Take the average score of multiple trials –Take the best score of multiple trials
Selecting a Norm-Referenced Score Comparison against… –Individuals Best example? –Tabled Values Match the group?
Types of Reliability Stability –Use Test-Retest Method Two administrations of a test with a calculation of how similar they are
Types of Reliability Internal Consistency –Use Split Half Method One group completes odd numbered components (or questions) while the other completes evens with a calculation of how similar they are
Factors Affecting Reliability Method of scoring – objective format is more reliable than subjective format Homogeneity of the group tested – more alike = reliable Length of test – longer tests are more reliable than shorter tests (number of questions/elements) Administrative procedures – clear directions, technique, motivation of subjects, good environment
Objectivity Objectivity is also referred to as rater reliability Objectivity is the close agreement between scores assigned by two or more judges Juggler please….
Factors Affecting Objectivity The clarity of the scoring system Neatness = 37% x difficulty factor (.87 / prime rate) Style = 42.489349834 – (IQ x shoe size) Originality = 3.14 x (E = MC 2 ) / date of birth
Factors Affecting Objectivity The degree to which judges can assign scores accurately (fairly, no bias) –Can you say, “French Skating Judge” eh?
Validity Validity is considered the most important characteristic of a test
Types of Validity Logical (content) Validity – validity that indicates a measurement instrument (test) actually measures the capacities about which conclusions are drawn –Examples: Tennis serve for accuracy versus 40 yd. run for time/speed in football or baseball
Types of Validity Construct Validity - validity for an instrument that measures a variable or factor that is not directly observable –Examples: Attitudes, feelings, motivation Learning new skills
Factors Affecting Validity Student characteristics –Examples: sex, age, experience Administrative procedures –Examples: unclear directions, poor weather Reliability –Example: same results after repeated test
When a A Test is Not Valid….. It is a waste of everyone’s time. A true judgment (evaluation) cannot be made. So….what’s the point?
A True Professional Values his/her field. Seeks the truth. Knows that bad data are worse than no data Wastes no one’s time.
Summary A Test Must Have Sensitivity Reliability Objectivity Validity To Be a Good Test
Tests and Their Administration Test Characteristics Administrative Concerns Participant Concerns Pre Test Procedures Administering the Test Post Test Procedures Individuals with Disabilities
Tests and Their Administration Test Characteristics Validity, Reliability, Objectivity Content Related Attributes –Important Attributes – a sample, not everything –Discrimination – best from better from good –Resemblance to the Activity - similarity –Specificity – single attribute vs. multiple attributes, ID’s limitations –Unrelated Measures – battery - different aspects – “independence”
Test Administration Administrative Concerns Mass Testability Minimal Practice Minimal Equipment Minimal Personnel Ease of Preparation Adequate Directions Norms / Criterion Useful Scores
Test Administration Participant Concerns Appropriateness to Participants Individual Scores Enjoyable Safety Confidentiality and Privacy Motivation
Test Administration Pretest Procedures -Knowing the Test -Developing Test Procedures -Developing Directions -Preparing the Participants -Planning Warm-up and Test Trials -Equipment and Facilities -Score Sheet (Recording) -Estimating Time Requirements
Test Administration Administering the Test Preparation Motivation Safety Recording Test Results
Test Administration Posttest Procedures Analyze Test Scores “Share” Information – highs vs. lows
Test Administration Individuals with Disabilities Cannot be compared to the typical student/person Few norm-referenced standards for evaluation Disabilities are varied – even within categories
Test Administration Individuals with Disabilities Disabilities Include: Mental Retardation – Mild, Moderate, Severe Serious Emotional Disturbance – Autism, Schizophrenia Orthopedic Impairment – Neurological, Musculoskeletal, Trauma Other Health Impaired – Asthma, Cardiovascular Disorders, Diabetes, Epilepsy, Obesity
Test Administration Individuals with Disabilities –Measure Physical Ability or Capacity Not learning, cognition, or language acquisition Find norm-referenced standards or validated tests
Summary Tests and Their Administration –Test Characteristics –Administrative Concerns –Participant Concerns –Pre Test Procedures –Administering the Test –Post Test Procedures –Individuals with Disabilities