(a) Explain the concept of exchangeability in probability. How does it differ from independence?
(b) Define skewness of a distribution. What are the different measures of skewness?
(i) In a frequency distribution, the coefficient of skewness based upon quartiles is 0.6. If the sum of the upper and lower quartiles is 100 and median is 38, find the values of Q1 and Q3.
(ii) Karl Pearson’s coefficient of skewness of a distribution is 0.32. If the standard deviation is 6.5 and mean is 29.6, determine the mode and the median of the distribution.