Errata  Page 4 : The second definition of mean is actually the median: "The mean value is the point at which half the probability (50%) is on one side of the mean and half on the other"
 Page 5: "The mean is the value at which the area is equal on both sides of the distribution." is true only for symmetric distributions, where it is equal to the median.
 pg 41 , 4.2.1, next to last sentence: "Thus, " 'one horizontal, two vertical' should be as noted in Figure 4.1 c.
 pg 51 para. 2, next to last sentence: : 'ice freezes' , should be 'water freezes' .

