But… it is still your responsibility Listening to Bob Marley makes me think of statistics and standardized testing….. Said no one ever But… it is still your responsibility

He put himself in the box Tonka Just for the record: He put himself in the box Bug

Standardized Testing (1) EDU 330: Educational Psychology Daniel Moos

Statistics and standard scores (1) Evaluating results of standardized tests through descriptive statistics (Measures of central tendency): (1) Mean: Average score (2) Median: Middle score in the distribution (3) Mode: Most frequent score (4) Range: Distance between top and bottom score in distribution

Statistics and standard scores (2) How should you use mean, median, mode, and range to interpret the results? 70, 80, 80, 80, 90 Mean: (400/5) = 80 Median: 80 Mode: Range: (90-70) = 20

Statistics and standard scores (3) How should you use mean, median, mode, and range to interpret the results? (continued) 20, 80, 80, 80, 90 Mean: (350/5) = 70 Median: 80 Mode: Range: (90-20) = 70

Statistics and standard scores (4) How should you use mean, median, mode, and range to interpret the results? (continued) 60, 60, 80, 100, 100 Mean: (400/5) = 80 Median: 80 Mode: 60, 100 Range: (100 – 60) = 40

Statistics and standard scores (5) Standard Deviation (SD): Statistical measure of spread of scores If data points are close to mean, then SD ≈ 0 If many data points are not close to mean, then SD > Formula Example on board Example: Mean of scores is 40 and standard deviation of 4 28 32 36 40 44 48 52 0% 2% 16% 84% 98% 100% 50%

Statistics and standard scores (6) Evaluating standardized tests through descriptive statistics, continued Standard Error of Measurement Due to measurement error, scores represent an approximation of student’s “true” score Example: Dan obtains a score of 54 on a standardized test. If the standard error of measurement is 3, then the range of Dan’s true score would be 51 to 57. Normal Distribution: Mean, median and mode are (roughly) equal; scores distribute themselves symmetrically in a bell-shaped curve

Statistics and standard scores (7) Raw Scores: What do they really mean? Percentiles (also call Percentile Ranks): ≠ percentages Rankings may not be equal; example: raw score of 58 = 90th percentile raw score of 56 = 80th percentile Raw score of 54 = 60th percentile Stanines: Range: 1 to 9 Stanine 5 = center of distribution One Stanine above/below = +/- 0.5 SD Stanine 6 = +0.5 SD; Stanine 4 = -0.5 SD; Stanine 8 = __SD Grade equivalents: Compares scores with particular age group (1st digit = grade, 2nd digit = month); Grade equivalent for total reading of 8.4 means __ ?

Statistics and standard scores (8):

Ending Exercises (1) A superintendent from New Hampshire says: “Standardized testing has its place -- but standardized testing should only be one piece of the picture of a child's performance or a school/district's performance at a given time. It is essential to educate ourselves and our communities about what standardized testing measures -- and what it does not measure…. I like the analogy that standardized testing is a snapshot that is one entry into an album about a child or school”

Ending Exercises (2) A high school science teacher from Washington, DC says: “I think they can limit the teaching environment because you end up  teaching to the test.  I think they can ultimately narrow the curriculum….  They do provide a basis, are consistent because the scorer cannot be biased since there is only one answer (that is, if it is multiple choice!)…. I  have always created my own tests, never have I used a ‘book test’...I  feel this way my students have the opportunity to demonstrate what  they know through short answer, longer essays, etc.”

Ending Exercises (3) A high school senior from Washington, DC says: “ I don’t know. I guess they are important, but I don’t think one test can really tell you how good a student I am…or even tell you how much I have learned. I just get real nervous when I take them because they are important, but it is kind of a one shot deal. I don’t think that is very fair.”