EXAMINATIONS OFFICE
NOl1h West University (Mafikeng Campus)
Private Bag X 2046
Ml1labatho
2735
FACULTY OF COMMERCE AND ADMINISTARTION
SCHOOL OF ECONOMIC AND DECISION SCIENCES
First Opportunity
Examination Summer 2008
Course Code STFM 329
Course Title Forecasting
Time allocated 3 hours
Marks 100
Department Statistics
First Examiner Mr P. G. Seaketso
Second Examiner Mr M. S. Sedupane
Instructions to candidates
1. Answer all questions
2. Scientific calculators may he used
J. Write Jogically~ legibly and lluillber your answers
4. Round your ans\vers to three decimal places
Candidates are not allowlcd to read the questions until they are told
to do so by the invigilator
, Question 1 [20]
As part of effort to forecast future gasoline sales. an operator of 5 independent gas
stations recorded the quarterly gasoline sales (in thousands of gallons) for the past 3
years. These are shown in the accoillpanying table.
Year Quar·l~r Gasoline Sales
1998 -
1
-
39
I
~ 37
-" --
')
-' --
61
--- .. _- ~-"-
4 58
1999 1 18
I
~ 56
82
')
,-- -'
4 27
2000 1 41
2 69
')
-) 49
I .. --
4 66
1. Calculate the 5-quarter nlo\:'ing averages and sho\\/ all your calculations. [10]
2. Fit a regression line and forecast for 4quaters of 200 1. [10]
Question 2 [30)
S11100thing nlethods 111ake no atten1pt to identify individual conlponents of the
underlying pattern in a tinle series. r\ tinle series {~\rf : r == 1.2..... " ltV }can consist of
four dit1erent con1ponents" nanlely" the trend 7~ " cyclical conlponent (If'' seasonal
a) f:xplain all the conlponents (121
b) 110\\1 does forecasting relate to planning? [51
c) Define the follo\ving ternlS: [ 15]
Seasonal Index. r)eseasonalise" T'inle Series forecasting"
'rrend /\nalysis and Exponential Snloothing.
d) Nanle and explain nlethods of forecasting. [8]
NOl1h West University (Mafikeng Campus)
Private Bag X 2046
Ml1labatho
2735
FACULTY OF COMMERCE AND ADMINISTARTION
SCHOOL OF ECONOMIC AND DECISION SCIENCES
First Opportunity
Examination Summer 2008
Course Code STFM 329
Course Title Forecasting
Time allocated 3 hours
Marks 100
Department Statistics
First Examiner Mr P. G. Seaketso
Second Examiner Mr M. S. Sedupane
Instructions to candidates
1. Answer all questions
2. Scientific calculators may he used
J. Write Jogically~ legibly and lluillber your answers
4. Round your ans\vers to three decimal places
Candidates are not allowlcd to read the questions until they are told
to do so by the invigilator
, Question 1 [20]
As part of effort to forecast future gasoline sales. an operator of 5 independent gas
stations recorded the quarterly gasoline sales (in thousands of gallons) for the past 3
years. These are shown in the accoillpanying table.
Year Quar·l~r Gasoline Sales
1998 -
1
-
39
I
~ 37
-" --
')
-' --
61
--- .. _- ~-"-
4 58
1999 1 18
I
~ 56
82
')
,-- -'
4 27
2000 1 41
2 69
')
-) 49
I .. --
4 66
1. Calculate the 5-quarter nlo\:'ing averages and sho\\/ all your calculations. [10]
2. Fit a regression line and forecast for 4quaters of 200 1. [10]
Question 2 [30)
S11100thing nlethods 111ake no atten1pt to identify individual conlponents of the
underlying pattern in a tinle series. r\ tinle series {~\rf : r == 1.2..... " ltV }can consist of
four dit1erent con1ponents" nanlely" the trend 7~ " cyclical conlponent (If'' seasonal
a) f:xplain all the conlponents (121
b) 110\\1 does forecasting relate to planning? [51
c) Define the follo\ving ternlS: [ 15]
Seasonal Index. r)eseasonalise" T'inle Series forecasting"
'rrend /\nalysis and Exponential Snloothing.
d) Nanle and explain nlethods of forecasting. [8]
