PSYC 3250 Chapter Notes - Chapter 5: South Dakota Highway 10, Percentile Rank, Emor

• School: University of Guelph
• Department: Psychology
• Course: PSYC 3250
• Professor: Deborah Powell

Document Summary

Scale: set of scores that might be reported for a test. Transformed score = constant + (weight x raw score) Changing unit of measurement (e. g. imperical vs metric) Example (be careful: may not initially seem like a linear transformation but it is) Generally easy to convert to percentiles note: only works with normal distribution. Solution change to t score = (z score x 10) + 50. Lots of fractional values harder to interpret: mean = 50, sd = 10, effective range = 20 80. Uses normal curve to create scale score values. Change the point of reference: express score in terms of where it is on a normal curve. Definition: percentage of population that falls below a given score. Notice that difference between score 1-2 is the same as 5-6 but the percentile jump is significantly different (6% versus 16%) Stanine ( standard + nine ): raw scores transformed from value between 1 9 based on percentile rank.