ECO-07 Solved Assignment For IGNOU
Course Title: Elements of Statistics
Following questions are answered in this solution:
Q. 1. What is statistical sampling and explain various methods of sampling.
Q. 2. “Statistical methods are most dangerous in the hands of the inexpert” Discuss with example.
Q. 3. (a) Find out missing frequencies in the following incomplete distribution:
Measurement 0-10 10-20 20-30 30-40 40-50
Frequency 3 ? 20 12 ?
4. a) Karl Pearson?s coefficient of skewness of a distribution is +0.32. Its standard deviation is 6.5 and
mean is 29.6. Find the mode and median of the distribution.
b) The mean and standar deviation of a set of 100 observations were worked out as 40 and 5 respectively by a computer who by mistake took the value 5o in place of 40 for one observation. Recalculate the correct mean and variance.
c) Find the missing information from the following
Particulars Group I Group II Group III Combined
Number 50 ? 90 200
Standard Deviation 6 7 ? 7.746
Mean 113 ? 115 116
d) Distinguish between U–shaped and bell-shaped data with suitable illustrations.
Q. 5. Write short notes on the following:
b) Mean deviation.
c) Standard deviation.
d) Lorenz Curve