Dibrugarh University - Business Statistics 2011

1.       (a)  Write down the differences between primary data and secondary data.
        (b)  Calculate mean and variance from the following data:
X     :
0-10
10-20
20-30
30-40
40-50
F      :
1
4
10
22
30
                                                                                                                                               
OR

        (c) What is the difference between absolute and relative measure of dispersion? Find the missing frequency from the following distribution when median is 32.5 marks:

Marks   :
10-20
20-30
30-40
40-50
50-60
No. of students:
3
5
----
3
1

        (d) Calculate from the following (i) Geometric mean (ii) Median and (iii) Mode:
                                                                                5,2,2,3,4,4,1

2.       (a)  What is regression line? Why are there two lines of regression?
        (b)  Calculate Karl Pearson’s coefficient of correlation from the following:
                                                N=10     ∑X=140   ∑Y=150
                                                ∑(X-10)2=180      ∑(Y-15)2=215
                                                ∑(X-10) (Y-15) =60

                                                                                                                Or

        (c)   Write down the difference between correlation and regression.
        (d)  Calculate coefficient of correlation from the following data:

Value of X:
1
2
3
4
5
6
7
8
9
10
Value of Y:
46
42
38
34
30
26
22
18
14
10

3.       (a)  Define index number and state its uses.
        (b)  Why is Fisher’s index number called ideal index number? Calculate Fisher’s index number? Calculate Fisher’s index number from the following data:
Commodity
Price
2003
Quantity
2003
Price
2005
Quantity
2005
A
B
C
D
E
8
10
5
4
4
10
12
8
14
5
10
12
8
14
5
12
8
5
3
25
               
       






Or
        (c)   State the limitations of index number.
        (d)  Calculate (i) price index (according to Laspeyres’ formula) and (ii) quantity index (according to Paasche’s index) using the following table:

       
Commodity
P0
q0
P1
q1
A
B
C
4
2
6
6
4
2
6
4
2
4
2
6

4.    (a)  From the following table, calculate trend values by 3-yearly weighted moving averages
                With weight 1, 2, 2 respectively:
               
Year:
1
2
3
4
5
6
7
Sales(Rs.)
2
4
5
7
8
10
13
       



        (b)  Discuss the components of a time series.

                                                                Or

        (c)   Find the trend values by 3-yearly moving average method from the following data:
               
Year:
1960
1961
1962
1963
1964
1965
1966
1967
1968
Sales:
5
7
9
12
11
10
8
12
13
        (d) Discuss the methods of measuring trends.

5.    (a)  Mention the purpose and assumptions of business forecasting.
        (b)  Discuss any three methods of forecasting.
                                                                Or
        (c)   Explain the concept of business forecasting.
        (d) Explain sales forecasting and demand forecasting.
                                                                               
                                                                                *****
                

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