9Standardized Tests and Teaching The Nature ofStandardized TestsThe Purposes of StandardizedTestsWhat Is aStandardized Test?Criteria forEvaluatingStandardized Tests15.9
10The Nature of Standardized Tests Have uniform procedures for administration and scoring.Allow comparison of student scores by age, grade level, local and national norms.Attempt to include material common across most classrooms.15.10
11Purposes of Standardized Tests Diagnose students’strengths andweaknessesProvide information forplanningand instructionProvide information aboutstudent progress andprogram placementContribute toaccountabilityHelp in programevaluation15.11
21Evaluating Standardized Tests Reliability – Are test scores stable, dependable and relatively free from error?Validity – Does the test measure what it is purported to measure?15.21
22Correlation r = + 0.37 Indicates strength of relationship (0.00 to 1.00)Correlationcoefficientr =+0.37OBJECTIVE 3-4| Describe positive and negative correlations and explain how correlational measures can aid the process of prediction.Correlation Coefficient is a statistical measure of relationship between two variables.Indicates directionof relationship(positive or negative)Psychology 7e in Modules
23Pearson correlation coefficient r = the Pearson coefficientr measures the amount that the two variables (X and Y) vary together (i.e., covary) taking into account how much they vary apartPearson’s r is the most common correlation coefficient; there are others.
24Computing the Pearson correlation coefficient To put it another way:Or
25Sum of Products of Deviations Measuring X and Y individually (the denominator):compute the sums of squares for each variableMeasuring X and Y together: Sum of ProductsDefinitional formulaComputational formulan is the number of (X, Y) pairs
26Correlation Coefficent: the equation for Pearson’s r:expanded form:
27ExampleWhat is the correlation between study time and test score:
31Correlation Coefficient Interpretation RangeStrength ofRelationshipPractically NoneLowModerateHigh ModerateVery High
32ReliabilityTest-retest: The extent to which a test yields the same score when given to a student on two different occasionsAlternate-forms: Two different forms of the same test on two different occasions to determine the consistency of the scoresSplit-half: Divide the test items into two halves; scores are compared to determine test score consistency15.32
35Methods of Studying Reliability Interrater Reliability- The consistency of a test tomeasure a skill, trait, or domain across examiners.This type of reliability is most important whenresponses are subjective or open-ended.
36Types of Validity…Content: Test’s ability to sample the content that is being measuredCriterion-related:Concurrent: The relation between a test’s score and other available criteriaPredictive: The relationship between test’s score and future performanceConstruct: The extent to which there is evidence that a test measures a particular construct15.36