Dibrugarh University - Business Statistics 2010


1.                   (a) Describe any one method of collecting primary data.
(b) Calculate standard deviation for the following data :

Mid-Value :
15
25
35
45
55
65
Frequency :
18
22
40
32
18
10
               
Or
                (c) A test in algebra is given to 400 high school children of whom 150 were boys and 250 were girls. The mean score of boys was 72 and that of girls was 73. Find the mean score of the combined group.
                (d) What is primary data and secondary data? Discuss any two methods of collecting primary data.
    2.        (a) Prove that Karl Pearson’s coefficient of correlation is independent of change of origin and change of scale.
                (b) From the following data, fit a regression line of Y on X :
X :
52
63
45
36
72
65
47
25
Y :
62
53
51
25
79
43
60
33
                                                                                                                Or
(c) What are the properties of coefficient of correlation? Explain the importance of statistics in Banking and Finance.
(d) Calculate Karl Pearson’s coefficient of correlation from the data given below :
X :
78
89
99
60
59
79
68
61
Y :
125
137
156
112
107
136
123
108

3.            (a) “Index numbers are economic barometers.” Explain it.
(b) What is the difference between a price index and a quantity index? How do the following stand as problems in the process of construction of index numbers – (i) selection of items, (ii) price quotations and (iii) selecting of formula?
Or
(c) Mention the two uses of cost of living index number and show that Fisher’s index satisfies time reversal test.
(d) Calculate price indices for the year 2003 from the following using – (i) Laspeyre’s method, (ii) Paasche’s method and (iii) Fisher’s method :
Commodity
2002
2003
Price
Quantity
Price
Quantity
A
B
C
D
2
5
4
2
8
10
14
19
4
6
5
2
6
5
10
13

4.            (a) Discuss the utility of the study of time series.
(b) Calculate trend using least square method from the following data :
  Year
1997
1998
1999
2000
2001
2002
2003
Sells (in lakh)
125
128
133
135
140
141
143
Or
                (c) Calculate seasonal indices from the following (use simple average method) :
Production (Tons)
Year
Ist Qtr
II Qtr
III Qtr
IV Qtr
2000
3.7
4.1
3.3
3.5
2001
3.7
3.9
3.6
3.6
2002
4.0
4.1
3.3
3.1
2003
3.3
4.4
4.0
4.0

d) Write short notes on :
(i) Least square method
(ii) Simple average method
(iii) Moving average method
5.            (a) A coin is tossed four times. What is the probability of getting two heads?
(b) Discuss the steps of forecasting.       
Or
(c) Explain the time series analysis and regression analysis method of forecasting.
(d) Explain any three theories of forecasting