QMS 102 Lecture Notes - Lecture 5: Statistical Inference, Interquartile Range, Variance
Document Summary
Give information on the spread of variability or the dispersion of the data values. Fail to tell the whole story about the distribution. Ignores the way in which data is distributed. Not affected by 1/2 extreme values as the range is. Used to measure variability, they also play a vital role in almost all statistical inference procedures. The more the data are spread out, the greater the range, variance, & standard deviation. The more the data are concentrated, the smaller the range, variance & standard deviation. If the values are all the same (no variation) all these measures will be zero.