Statistical Sciences 1023A/B Lecture Notes - Lecture 6: Symphony Of Ages, Standard Score, Standard Deviation

• School: Western University
• Department: Statistical Sciences
• Course: Statistical Sciences 1023A/B
• Professor: Jennifer Waugh

Document Summary

Normal distribution w/ mean of 0 of standard deviation of 1. Standardize values from a distribution to "standard normal distribution" n(0,1) Z = value to standardize (x) subtracted by mean of distribution (u) divided by standard deviation of origional distribution (o) Z score: number of standard deviations a value is from the mean of its distribution. Characterizes how far away a value is from its mean. Value (77%) minus the mean (75) divided by the standard deviation (4) = 2 divided by 4 therefore the z score = 0. 5 (very close to mean) Value (74%) minus the mean (68) divided by the standard deviation (10) = 6 divided by 10 = 0. 6. Achmed - he is only half a sd from the mean therefore achmed should pay for dinner. If your data has a normal distribution approx 68% of area under the curve is +/- +/- 2 sd from the mean = 95% of ppl under the curve.