18. In a study of author productivity (“Lotka’s Test,” Collection Mgmt., 1982: 111–118), a large number of authors were classified according to the number of articles they had published during a certain period. The results were presented in the accompanying frequency distribution:

Number of papers 1 2 3 4 5 6 7 8 Frequency 784 204 127 50 33 28 19 19 Number of papers 9 10 11 12 13 14 15 16 17 Frequency 6 7 6 7 4 4 5 3 3 x 5 number

a. Construct a histogram corresponding to this frequency distribution. What is the most interesting feature of the shape of the distribution?

b. What proportion of these authors published at least five papers? At least ten papers? More than ten papers?

c. Suppose the five 15s, three 16s, and three 17s had been lumped into a single category displayed as “ .”

Would you be able to draw a histogram? Explain.

d. Suppose that instead of the values 15, 16, and 17 being listed separately, they had been combined into a 15–17 category with frequency 11. Would you be able to draw a histogram? Explain.