Mean of 100 items is found to be 30. If at the time of calculation, two items are wrongly taken as 32 and 12 instead of 23 and 11, find the correct mean.
Discuss the merits and demerits of Karl Pearson's coefficient of correlation.
What is Spearman's rank correlation? Bring out its usefulness. How does the coefficient differ from Karl Pearson's coefficient of correlation?