game theory problems by an alternative simplex method

IJRET: International Journal of Research in Engineering and Technology
eISSN: 2319-1163 | pISSN: 2321-7308
GAME THEORY PROBLEMS BY AN ALTERNATIVE SIMPLEX
METHOD
Kirtiwant P. Ghadle1, Tanaji S. Pawar2
1
Associate Professor, Department of Mathematics, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad,
Maharashtra, India
2
Research Student, Department of Mathematics, Dr. Babasaheb Ambedkar Marathwada University, Aurangabad,
Maharashtra, India
Abstract
In this paper, an alternative method for the solution of game problems is introduced. This method is easy to solve game problem
which does not have a saddle point. It is powerful method to reduce number of iterations and save valuable time.
Keywords: Linear programming problem, Optimal solution, Alternative simplex method, and Game problem.
--------------------------------------------------------------------***-----------------------------------------------------------------1. INTRODUCTION
Todayโ€™s life is a full of struggle and competitions. A great
variety of competitive situations is commonly seen. What
should be the bid to win a big government job in the pace of
competition from several jobs? Game must be thought of, in
abroad sense, not as a kind of sport but as competitive
situation, a kind of conflict in which somebody must win
and somebody must lose.
John Von Neumann suggestion is to solve the game theory
problems on the maximum losses. Dantzig [1] suggestion is
to choose that entering vector corresponding to which
๐‘ง๐‘— โˆ’ ๐‘๐‘— is most negative. Khobragade et al. [2, 3, 4]
suggestion is to choose that entering vector corresponding to
which
( ๐‘ง๐‘— โˆ’ ๐‘๐‘— ) ๐œƒ ๐‘—
๐‘๐‘—
is most negative.
In this paper, an attempt has been made to solve linear
programming problem (LPP) by new method which is an
alternative for simplex method. This method is different
from Khobragade et al. Method.
2. SOLUTION OF M x N RECTANGULAR
GAME PROBLEM
By fundamental theorem of rectangular games, if mixed
strategies are allowed, there always exists a value of game.
( i.e. ๐‘‰ = ๐‘‰ = ๐‘‰ ).
Let the two person zero sum game be defined as follows:
Player B
๐‘Ž11 โ‹ฏ ๐‘Ž1๐‘›
โ‹ฑ
โ‹ฎ
Player A โ‹ฎ
๐‘Ž๐‘š1 โ‹ฏ ๐‘Ž๐‘š๐‘›
Then
and
๐‘1 + ๐‘2 + ๐‘3 + โ€ฆ + ๐‘๐‘š = 1
๐‘ž1 + ๐‘ž2 + ๐‘ž3 + โ€ฆ + ๐‘ž๐‘› = 1,
Where ๐‘๐‘– โ‰ฅ 0 and ๐‘ž๐‘— โ‰ฅ 0 for all ๐‘–, ๐‘—.
Let the game can be defined by LPP as given below:
1
For player A: Minimize ๐‘‹ = ๐‘ฅ1 + ๐‘ฅ2 + โ‹ฏ + ๐‘ฅ๐‘š or =
๐‘‰
Subject to: ๐‘Ž11 ๐‘ฅ1 + ๐‘Ž21 ๐‘ฅ2 + โ‹ฏ + ๐‘Ž๐‘š1 ๐‘ฅ๐‘š โ‰ฅ 1
๐‘Ž12 ๐‘ฅ1 + ๐‘Ž22 ๐‘ฅ2 + โ‹ฏ + ๐‘Ž๐‘š2 ๐‘ฅ๐‘š โ‰ฅ 1
..................................................
..................................................
๐‘Ž1๐‘› ๐‘ฅ1 + ๐‘Ž2๐‘› ๐‘ฅ2 + โ‹ฏ + ๐‘Ž๐‘š๐‘› ๐‘ฅ๐‘š โ‰ฅ 1
๐‘ฅ1 , ๐‘ฅ2 , โ€ฆ , ๐‘ฅ๐‘š โ‰ฅ 0.
1
For Player B: Maximize ๐‘Œ = ๐‘ฆ1 + ๐‘ฆ2 + โ‹ฏ + ๐‘ฆ๐‘› or =
๐‘‰
Subject to: ๐‘Ž11 ๐‘ฆ1 + ๐‘Ž12 ๐‘ฆ2 + โ‹ฏ + ๐‘Ž1๐‘› ๐‘ฆ๐‘š โ‰ค 1
๐‘Ž21 ๐‘ฆ1 + ๐‘Ž22 ๐‘ฆ2 + โ‹ฏ + ๐‘Ž2๐‘› ๐‘ฆ๐‘š โ‰ค 1
..................................................
..................................................
๐‘Ž๐‘š1 ๐‘ฆ1 + ๐‘Ž๐‘š2 ๐‘ฆ2 + โ‹ฏ + ๐‘Ž๐‘š๐‘› ๐‘ฆ๐‘š โ‰ค 1
๐‘ฅ1 , ๐‘ฅ2 , โ€ฆ , ๐‘ฅ๐‘š โ‰ฅ 0.
To find the optimal solution of the above LPP, it has been
observed that the player Bโ€™s problem is exactly the dual of
the player Aโ€™s problem. The optimal solution of one
problem will automatically give the optimal solution to the
other. The player Bโ€™s problem can be solved by an
alternative simplex method while player Aโ€™s problem can be
solved by an alternative dual simplex method [7].
Let ๐‘1 , ๐‘2 , โ€ฆ , ๐‘๐‘š and ๐‘ž1 , ๐‘ž2 , โ€ฆ , ๐‘ž๐‘› be the probabilities of
two players A and B, to select their pure strategies. i.e.
๐‘†๐ด = ๐‘1 , ๐‘2 , โ€ฆ , ๐‘๐‘š and ๐‘†๐ต = (๐‘ž1 , ๐‘ž2 , โ€ฆ , ๐‘ž๐‘› ).
_______________________________________________________________________________________
Volume: 03 Issue: 05 | May-2014, Available @ http://www.ijret.org
900
IJRET: International Journal of Research in Engineering and Technology
3. SOLVED PROBLEMS
1
1
3.1: Problem 1
1
๐‘ฆ2
๐‘ฆ1
๐‘ฆ3
๐‘ฆ2
eISSN: 2319-1163 | pISSN: 2321-7308
1/3
0
1
0
0
0
1/3
1/2
1
0
0
1/2
0
0
1/4
0
1
0
0
1/4
0
1/3
0
0
1
0
0
1/3
-
Solve the following game by linear programming technique:
1
Player B
1 โˆ’1
Player A โˆ’1 โˆ’1
โˆ’1 2
Since all rows and column are ignored, hence an optimum
solution has been reached. Therefore optimum solution is:
โˆ’1
3 .
โˆ’1
Solution: The given game has ๐‘‰= -1, ๐‘‰ = 1. It does not
possess the saddle point and the value of game -1 < V < 1.
Adding a suitable constant k = 1 to all the elements of
payoff of matrix.
Then, the linear programming problem can be written as:
1
For player A: Minimize ๐‘‹ = ๐‘ฅ1 + ๐‘ฅ2 + ๐‘ฅ3 or =
๐‘‰
Subject to: 2๐‘ฅ1 โ‰ฅ 1
3๐‘ฅ3 โ‰ฅ 1
4๐‘ฅ2 โ‰ฅ 1.
๐‘ฅ1 , ๐‘ฅ2 , ๐‘ฅ3 โ‰ฅ 0.
LPP is in standard form for player B:
1
Maximize ๐‘Œ = ๐‘ฆ1 + ๐‘ฆ2 + ๐‘ฆ3 or =
๐‘‰
Subject to: 2๐‘ฆ1 + ๐‘ 1 = 1
4๐‘ฆ3 + ๐‘ 2 = 1
3๐‘ฆ2 + ๐‘ 3 = 1.
๐‘ฆ1 , ๐‘ฆ2 , ๐‘ฆ3 , ๐‘ 1 , ๐‘ 2 , ๐‘ 3 โ‰ฅ 0.
0
0
1
0
0
1
๐‘ 1
๐‘ 2
๐‘ 3
๐‘ 1
๐‘ฆ3
๐‘ 3
๐‘ 1
๐‘ฆ3
1
12
๐‘Œ
13
1
โˆ’1=โˆ’ .
13
The optimal strategies for player A are obtained from final
table of the above problem. This is given by duality rules:
๐‘‹=๐‘Œ=
13
,
12
1/2
1
0 = ,
2
0
๐‘ฅ1 = 1
1
1
๐‘ฅ2 = 1
1
0
1
1 1/4 = ,
4
0
๐‘ฅ3 = 1
1
1
0
1
0 = .
3
1/3
Hence,
1
1
๐‘ฅ1
6
๐‘ฅ2
3
2
๐‘1 =
=
=
, ๐‘2 =
= 4 = ,
13
13
๐‘‹
13
๐‘‹
13
12
12
Simplex Table:
0
.
๐‘ฆ3
1/4
3
=
=
๐‘Œ
12/13 13
and ๐‘‰ = โˆ’ ๐‘˜ =
Where ๐‘ 1 , ๐‘ 2 , ๐‘ 3 are slack variables.
0
12
๐‘ž3 =
For Player B:
1
Maximize ๐‘Œ = ๐‘ฆ1 + ๐‘ฆ2 + ๐‘ฆ3 or =
๐‘‰
Subject to: 2๐‘ฆ1 โ‰ค 1
4๐‘ฆ3 โ‰ค 1
3๐‘ฆ2 โ‰ค 1.
๐‘ฆ1 , ๐‘ฆ2 , ๐‘ฆ3 โ‰ฅ 0.
๐‘ฆ1
13
4
1
๐‘ฆ2
4
๐‘ž2 =
= 3 = ,
12
๐‘Œ
13
13
๐‘†๐ด = ๐‘1 , ๐‘2 , ๐‘3 and ๐‘†๐ต = (๐‘ž1 , ๐‘ž2 , ๐‘ž3 ), where ๐‘1 + ๐‘2 +
๐‘3 = 1, ๐‘ž1 + ๐‘ž2 + ๐‘ž3 = 1.
๐‘‹๐ต
1
3
1
๐‘ฆ1
6
๐‘ž1 =
= 2 = ,
13 13
๐‘Œ
12
Let the strategies of two players be:
BVS
1
2
Thus, the optimal strategies for player B are:
Player B
2 0 0
Player A 0 0 4
0 3 0
๐ถ๐ต
1
๐‘ฆ1 = , ๐‘ฆ2 = , ๐‘ฆ3 = . Max. ๐‘Œ =
๐‘ฆ2
๐‘ฆ3
๐‘ 1
๐‘ 2
๐‘ 3
Ratio
1
2
0
0
1
0
0
-
1
0
0
4
0
1
0
1/4โ†’
1
0
3
0
0
0
1
-
1
2
0
0
1
0
0
-
1/4
0
0
1
0
1/4
0
-
1
0
3
0
0
0
1
1/3โ†’
1
2
0
0
1
0
0
1/2โ†’
1/4
0
0
1
0
1/4
0
-
๐‘3 =
๐‘ฅ3
1/3
4
=
=
๐‘‹ 13/12 13
and ๐‘‰ =
12
13
โˆ’1=
โˆ’1
13
.
_______________________________________________________________________________________
Volume: 03 Issue: 05 | May-2014, Available @ http://www.ijret.org
901
IJRET: International Journal of Research in Engineering and Technology
3.2: Problem 2:
0
Two companies P and Q are competing for the same
product. Their different strategies are given in the following
payoff matrix:
3/11
0
0
13/11
-
1
1
๐‘ฆ1
3/11
1
2/11
0
3/13โ†’
-
1/11
7/11
-
0
4/11
1/11
1
1
Player Q
1 2 4
Player P 2 2 1 .
3 1 1
๐‘ 2
eISSN: 2319-1163 | pISSN: 2321-7308
๐‘ฆ3
๐‘ฆ2
1/13
0
0
1
4/13
-5/13
2/13
3/13
0
1
0
-
11/13
-
1/13
1
๐‘ฆ1
3/13
1
0
0
7/13
-
-2/13
6/13
1/13
Use linear programming to determine the best strategies for
both the companies.
Solution: The given game has ๐‘‰= 1, ๐‘‰ = 2. It does not
possess the saddle point and the value of game 1 < V < 2.
Here, the payoff matrix is already non-negative.
Since all rows and column are ignored, hence an optimum
solution has been reached. Therefore optimum solution is:
๐‘ฆ1 =
3
13
, ๐‘ฆ2 =
3
13
, ๐‘ฆ3 =
1
13
. Max. ๐‘Œ =
7
13
.
Thus, the optimal strategies for player B are:
Let the strategies of two players be:
๐‘ž1 =
๐‘†๐ด = ๐‘1 , ๐‘2 , ๐‘3 and ๐‘†๐ต = (๐‘ž1 , ๐‘ž2 , ๐‘ž3 ), where ๐‘1 + ๐‘2 +
๐‘3 = 1, ๐‘ž1 + ๐‘ž2 + ๐‘ž3 = 1.
3
๐‘ฆ1 13 3
=
= ,
7
๐‘Œ
7
13
3
๐‘ฆ2 13 3
๐‘ž2 =
=
= ,
7
๐‘Œ
7
13
Then, the linear programming problem can be written as:
For player A:
1
Minimize ๐‘‹ = ๐‘ฅ1 + ๐‘ฅ2 + ๐‘ฅ3 or =
๐‘‰
Subject to: ๐‘ฅ1 + 2๐‘ฅ2 + 3๐‘ฅ3 โ‰ฅ 1
2๐‘ฅ1 + 2๐‘ฅ2 + ๐‘ฅ3 โ‰ฅ 1
4๐‘ฅ1 + ๐‘ฅ2 + ๐‘ฅ3 โ‰ฅ 1.
๐‘ฅ1 , ๐‘ฅ2 , ๐‘ฅ3 โ‰ฅ 0.
๐‘ž3 =
๐‘ฆ3 1/13 1
=
=
๐‘Œ
7/13 7
1
13
๐‘Œ
7
and ๐‘‰ = โˆ’ ๐‘˜ =
โˆ’0=
13
7
.
The optimal strategies for player A are obtained from final
table of the above problem. This is given by duality rules:
For Player B:
1
Maximize ๐‘Œ = ๐‘ฆ1 + ๐‘ฆ2 + ๐‘ฆ3 or =
๐‘‰
Subject to: ๐‘ฆ1 + 2๐‘ฆ2 + 4๐‘ฆ3 โ‰ค 1
2๐‘ฆ1 + 2๐‘ฆ2 + ๐‘ฆ3 โ‰ค 1
3๐‘ฆ1 + ๐‘ฆ2 + ๐‘ฆ3 โ‰ค 1.
๐‘ฆ1 , ๐‘ฆ2 , ๐‘ฆ3 โ‰ฅ 0.
๐‘‹=๐‘Œ=
1
4/13
2
1 โˆ’1/13 = ,
13
โˆ’1/13
๐‘ฅ2 = 1
1
โˆ’5/13
4
1 11/13 = ,
13
โˆ’2/13
๐‘ฅ3 = 1
1
2/13
1
1 โˆ’7/13 = .
13
6/13
๐‘ฅ1 = 1
LPP is in standard form for player B:
1
Maximize ๐‘Œ = ๐‘ฆ1 + ๐‘ฆ2 + ๐‘ฆ3 or =
๐‘‰
Subject to: ๐‘ฆ1 + 2๐‘ฆ2 + 4๐‘ฆ3 + ๐‘ 1 = 1
2๐‘ฆ1 + 2๐‘ฆ2 + ๐‘ฆ3 + ๐‘ 2 = 1
3๐‘ฆ1 + ๐‘ฆ2 + ๐‘ฆ3 + ๐‘ 3 = 1.
๐‘ฆ1 , ๐‘ฆ2 , ๐‘ฆ3 , ๐‘ 1 , ๐‘ 2 , ๐‘ 3 โ‰ฅ 0.
Where ๐‘ 1 , ๐‘ 2 , ๐‘ 3 are slack variables.
7
,
13
Simplex Table:
๐ถ๐ต
0
0
0
1
0
0
1
BVS
๐‘ 1
๐‘ 2
๐‘ 3
๐‘ฆ3
๐‘ 2
๐‘ 3
๐‘ฆ3
๐‘‹๐ต
๐‘ฆ1
๐‘ฆ2
๐‘ฆ3
๐‘ 1
๐‘ 2
๐‘ 3
Ratio
1
1
2
4
1
0
0
1/4โ†’
1
2
2
1
0
1
0
1
1
3
1
1
0
0
1
1
1/4
1/4
1/2
1
1/2
0
0
3/4
7/4
3/2
0
-1/4
1
0
3/7
3/4
11/4
1/2
0
-1/4
0
1
3/11โ†’
2/11
0
5/11
1
3/11
0
-
Hence,
1/11
2
4
๐‘ฅ1 13 2
๐‘ฅ2 13 4
๐‘1 =
=
= , ๐‘2 =
=
= ,
7
7
๐‘‹
7
๐‘‹
7
13
13
๐‘3 =
๐‘ฅ3 1/13 1
=
=
๐‘‹ 7/13 7
and ๐‘‰ =
13
7
โˆ’0=
13
7
.
_______________________________________________________________________________________
Volume: 03 Issue: 05 | May-2014, Available @ http://www.ijret.org
902
IJRET: International Journal of Research in Engineering and Technology
eISSN: 2319-1163 | pISSN: 2321-7308
3.3: Problem 3:
14/31
Solve the following game by linear programming technique:
1
1
1
Player B
3 โˆ’1
Player A โˆ’3 3
โˆ’4 โˆ’3
1
โˆ’3
โˆ’1 .
3
๐‘ฆ3
๐‘ฆ1
๐‘ฆ2
๐‘ฆ3
7/62
0
6/31
1
-1/62
0
4/31
1/14
1
0
0
1/7
-1/14
0
11/196
0
1
0
-3/98
31/196
-1/14
5/49
0
0
1
-1/98
-3/98
1/7
Since all rows and column are ignored, hence an optimum
solution has been reached. Therefore optimum solution is:
Solution: The given game has ๐‘‰= -3, ๐‘‰ = 3. It does not
possess the saddle point and the value of game -3 < V < 3.
To make this payoff matrix as positive, adding a suitable
constant k = 5 to all the elements of payoff of matrix.
๐‘ฆ1 =
1
14
11
, ๐‘ฆ2 =
196
, ๐‘ฆ3 =
5
49
. Max. ๐‘Œ =
1
๐‘ฆ1
14
14
๐‘ž1 =
=
= ,
45
๐‘Œ
45
196
Let the strategies of two players be:
๐‘†๐ด = ๐‘1 , ๐‘2 , ๐‘3 and ๐‘†๐ต = (๐‘ž1 , ๐‘ž2 , ๐‘ž3 ), where ๐‘1 + ๐‘2 +
๐‘3 = 1, ๐‘ž1 + ๐‘ž2 + ๐‘ž3 = 1.
11
๐‘ฆ2 196 11
๐‘ž2 =
=
= ,
45
๐‘Œ
45
196
Then, the linear programming problem can be written as:
1
๐‘ฅ1 = 1
๐‘ฅ2 = 1
๐‘ฅ3 = 1
๐‘ฆ3
๐‘ 1
๐‘ 2
๐‘ 3
Ratio
V
0
0
1
0
0
1
0
๐‘ 1
๐‘ 2
๐‘ 3
๐‘ฆ1
๐‘ 2
๐‘ 3
๐‘ฆ1
๐‘ 2
45
1
1
1
45
,
196
1/7
5
1 โˆ’3/98 = ,
49
โˆ’1/98
โˆ’1/14
11
,
1 31/196 =
196
โˆ’3/98
0
1
1 โˆ’1/14 = .
14
1/7
5
11
๐‘ฅ1
20
๐‘ฅ2 196 11
49
๐‘1 =
=
=
,๐‘ =
=
= ,
45
45
๐‘‹
45 2
๐‘‹
45
196
196
S
0
29
โˆ’5 =โˆ’ .
Hence,
Simplex Table:
๐‘ฆ2
45
๐‘‹=๐‘Œ=
where ๐‘ 1 , ๐‘ 2 , ๐‘ 3 are slack variables.
๐‘ฆ1
196
The optimal strategies for player A are obtained from final
table of the above problem. This is given by duality rules:
LPP is in standard form for player B:
Maximize ๐‘Œ = ๐‘ฆ1 + ๐‘ฆ2 + ๐‘ฆ3
Subject to: 8๐‘ฆ1 + 4๐‘ฆ2 + 3๐‘ฆ3 + ๐‘ 1 = 1
2๐‘ฆ1 + 8๐‘ฆ2 + 4๐‘ฆ3 + ๐‘ 2 = 1
๐‘ฆ1 + 2๐‘ฆ2 + 8๐‘ฆ3 + ๐‘ 3 = 1.
๐‘ฆ1 , ๐‘ฆ2 , ๐‘ฆ3 , ๐‘ 1 , ๐‘ 2 , ๐‘ 3 โ‰ฅ 0.
๐‘‹๐ต
1
๐‘Œ
and ๐‘‰ = โˆ’ ๐‘˜ =
For Player B:
1
Maximize ๐‘Œ = ๐‘ฆ1 + ๐‘ฆ2 + ๐‘ฆ3 or =
๐‘‰
Subject to: 8๐‘ฆ1 + 4๐‘ฆ2 + 3๐‘ฆ3 โ‰ค 1
2๐‘ฆ1 + 8๐‘ฆ2 + 4๐‘ฆ3 โ‰ค 1
๐‘ฆ1 + 2๐‘ฆ2 + 8๐‘ฆ3 โ‰ค 1.
๐‘ฆ1 , ๐‘ฆ2 , ๐‘ฆ3 โ‰ฅ 0.
B
.
๐‘ฆ3
5/49
20
=
=
๐‘Œ
45/196 45
๐‘ž3 =
For player A: Minimize ๐‘‹ = ๐‘ฅ1 + ๐‘ฅ2 + ๐‘ฅ3 or =
๐‘‰
Subject to: 8๐‘ฅ1 + 2๐‘ฅ2 + ๐‘ฅ3 โ‰ฅ 1
4๐‘ฅ1 + 8๐‘ฅ2 + 2๐‘ฅ3 โ‰ฅ 1
2๐‘ฅ1 + 4๐‘ฅ2 + 8๐‘ฅ3 โ‰ฅ 1.
๐‘ฅ1 , ๐‘ฅ2 , ๐‘ฅ3 โ‰ฅ 0.
45
196
Thus, the optimal strategies for player B are:
Player B
8 4 2
Player A 2 8 4
1 2 8
๐ถ๐ต
โ†’
1
8
4
2
1
0
0
1/8โ†’
1
2
8
4
0
1
0
1/2
1
1
2
8
0
0
1
1
1/8
1
1/2
1/4
1/8
0
0
3/4
0
7
7/2
-1/4
1
0
3/14
7/8
0
3/2
31/4
-1/8
0
1
7/62โ†’
3/31
1
14/31
0
4/31
0
-1/31
11/31
0
196/31
0
-6/31
1
-
๐‘3 =
๐‘ฅ3
1/14
14
=
=
๐‘‹ 45/196 45
and ๐‘‰ =
196
45
29
โˆ’5 =โˆ’ .
45
11/196
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Volume: 03 Issue: 05 | May-2014, Available @ http://www.ijret.org
903
IJRET: International Journal of Research in Engineering and Technology
3.4: Problem 4:
0
Two companies P and Q are competing for the same
product. Their different strategies are given in the following
payoff matrix:
-1
-1
0
๐‘ 2
๐‘ฅ1
๐‘ฅ3
๐‘ 2
eISSN: 2319-1163 | pISSN: 2321-7308
-1/2
0
-3/2
-1/2
0
0
-1/2
1/4
1
1/4
1/4
0
1
-1/4
3/11
0
7/11
1
-4/11
0
1/11
-4/11
0
-
0
-2/11
1
-5/11
13/11
Player Q
โˆ’1 0
Player P
0
0
1 โˆ’1
-1
2
โˆ’1 .
โˆ’1
-1
-1
๐‘ฅ1
๐‘ฅ3
๐‘ฅ2
-1
Solution: The given game has ๐‘‰= -1, ๐‘‰ = 0. It does not
possess the saddle point and the value of game -1 < V < 0.
To make this payoff matrix as positive, adding a suitable
constant k = 2 to all the elements of payoff of matrix.
๐‘ฅ1
1
-2/13
4/13
0
1
0
2/13
-
5/13
2/13
1
0
0
1/13
2
13
, ๐‘ฅ2 =
4
13
, ๐‘ฅ3 =
1/13
-4/13
1
13
. Min. ๐‘‹ =
7
13
.
๐‘ฅ2
๐‘ฅ3
-1
-1
-2
-3
1
-1
-2
-2
-1
0
-1
-4
-1
-1
-3/4
0
-7/4
-
13
7
1
โˆ’2=โˆ’ .
7
The optimal strategies for player B are obtained from final
table of the above problem. This is given by duality rules:
7
,
13
โˆ’6/13
3
2/13 =
,
13
1/13
๐‘ฆ1 = โˆ’1
โˆ’1
โˆ’1
๐‘ฆ2 = โˆ’1
โˆ’1
7/13
3
,
โˆ’1 โˆ’11/13 =
13
1/13
โˆ’1
โˆ’2/13
1
.
โˆ’1 5/13 =
13
โˆ’4/13
๐‘ฆ3 = โˆ’1
Hence,
3
3
๐‘ฆ1 13 3
๐‘ฆ2 13 3
๐‘ž1 =
=
= , ๐‘ž2 =
=
= ,
7
7
๐‘Œ
7
๐‘Œ
7
13
13
Simplex Table:
๐‘ฅ1
1
๐‘‹
and = โˆ’ ๐‘˜ =
where ๐‘ 1 , ๐‘ 2 , ๐‘ 3 are slack variables.
๐‘‹๐ต
๐‘ฅ3 1/13 1
=
=
๐‘‹ 7/13 7
๐‘‹=๐‘Œ=
LPP is in standard form for player A:
Max. ๐‘ โˆ— = ๐‘ฅ1 โˆ’ ๐‘ฅ2 โˆ’ ๐‘ฅ3
Subject to: โˆ’๐‘ฅ1 โˆ’ 2๐‘ฅ2 โˆ’ 3๐‘ฅ3 + ๐‘ 1 = โˆ’1
โˆ’2๐‘ฅ1 โˆ’ 2๐‘ฅ2 โˆ’ ๐‘ฅ3 + ๐‘ 2 = โˆ’1
โˆ’4๐‘ฅ1 โˆ’ ๐‘ฅ2 โˆ’ ๐‘ฅ3 + ๐‘ 3 = โˆ’1
๐‘ฅ1 , ๐‘ฅ2 , ๐‘ฅ3 , ๐‘ 1 , ๐‘ 2 , ๐‘ 3 โ‰ฅ 0.
0
-3/11
7/13
๐‘3 =
For player A: Minimize ๐‘‹ = ๐‘ฅ1 + ๐‘ฅ2 + ๐‘ฅ3 or =
๐‘‰
Subject to: ๐‘ฅ1 + 2๐‘ฅ2 + 3๐‘ฅ3 โ‰ฅ 1
2๐‘ฅ1 + 2๐‘ฅ2 + ๐‘ฅ3 โ‰ฅ 1
4๐‘ฅ1 + ๐‘ฅ2 + ๐‘ฅ3 โ‰ฅ 1.
๐‘ฅ1 , ๐‘ฅ2 , ๐‘ฅ3 โ‰ฅ 0.
Min. ๐‘ = - Max. โˆ’๐‘ , โˆ’๐‘ = ๐‘ โˆ—
Max. ๐‘ โˆ— = โˆ’๐‘ฅ1 โˆ’ ๐‘ฅ2 โˆ’ ๐‘ฅ3
Subject to: โˆ’๐‘ฅ1 โˆ’ 2๐‘ฅ2 โˆ’ 3๐‘ฅ3 โ‰ค โˆ’1
โˆ’2๐‘ฅ1 โˆ’ 2๐‘ฅ2 โˆ’ ๐‘ฅ3 โ‰ค โˆ’1
โˆ’4๐‘ฅ1 โˆ’ ๐‘ฅ2 โˆ’ ๐‘ฅ3 โ‰ค โˆ’1.
๐‘ฅ1 , ๐‘ฅ2 , ๐‘ฅ3 โ‰ฅ 0.
0
0
-6/13
2
4
๐‘ฅ1 13 2
๐‘ฅ2 13 4
๐‘1 =
=
= , ๐‘2 =
=
= ,
7
7
๐‘‹
7
๐‘‹
7
13
13
Then, the linear programming problem can be written as:
0
1/11
1
Thus, the optimal strategies for player A are:
๐‘†๐ด = ๐‘1 , ๐‘2 , ๐‘3 and ๐‘†๐ต = (๐‘ž1 , ๐‘ž2 , ๐‘ž3 ), where ๐‘1 + ๐‘2 +
๐‘3 = 1, ๐‘ž1 + ๐‘ž2 + ๐‘ž3 = 1.
๐‘ 1
๐‘ 2
๐‘ 3
๐‘ 1
0
0
๐‘ฅ1 =
Let the strategies of two players be:
0
1/11
0
Since all rows and column are ignored, hence an optimum
solution has been reached. Therefore optimum solution is:
Player B
1 2 4
Player A 2 2 1
3 1 1
BVS
1
1/13
11/13
Use linear programming to determine the best strategies for
both the companies.
๐ถ๐ต
2/11
๐‘ 1
๐‘ 2
๐‘ 3
Ratio
0
0
1
1
0
1/2
0
0
1
1/4โ†’
1
0
-1/4
๐‘ž3 =
๐‘ฆ3 1/13 1
=
=
๐‘Œ
7/13 7
and ๐‘‰ =
13
7
1
โˆ’2=โˆ’ .
7
11/4
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Volume: 03 Issue: 05 | May-2014, Available @ http://www.ijret.org
904
IJRET: International Journal of Research in Engineering and Technology
eISSN: 2319-1163 | pISSN: 2321-7308
4. CONCLUSIONS
An alternative method for game theory problems to obtain
the solution of linear programming problem has been
derived. This technique is useful to apply on numerical
problems, reduces the labour work and save valuable time.
REFERENCES
[1]. G. B. Dantzig: Maximization of linear function of
variables subject to linear inequalities, In: 21-Ed. Koopman
Cowls Commission Monograph, 13, John Wiley and Sons,
Inc., New Yark (1951).
[2]. K. G. Lokhande, N. W. Khobragade, P. G. Khot:
Simplex Method: An Alternative Approach, International
Journal of Engineering and Innovative Technology, Volume
3, Issue 1, P: 426-428 (2013).
[3]. N. V. Vaidya, N. W. Khobragade: Solution of Game
Problems Using New Approach, IJEIT, Vol. 3, Issue 5,
2013.
[4]. N. W. Khobragade and P. G. Khot: Alternative
Approach to the Simplex Method-II, Acta Ciencia Indica,
Vol.xxx IM, No.3, 651, India (2005).
[5]. S. D. Sharma: Operation Research, Kedar Nath Ram
Nath, 132, R. G. Road, Meerut-250001 (U.P.), India.
[6]. S. I. Gass: Linear Programming, 3/e, McGraw-Hill
Kogakusha, Tokyo (1969).
[7]. K. P. Ghadle, T. S. Pawar, N. W. Khobragade: Solution
of Linear Programming Problem by New Approach, IJEIT,
Vol.3, Issue 6. Pp.301-307, 2013
BIOGRAPHIES
Mr. Tanaji S. Pawar, Research student,
Department of mathematics, Dr. Babasaheb
Ambedkar
Marathwada
University,
Aurangabad.
Dr. K. P. Ghadle for being M.Sc in Maths he
attained Ph.D. He has been teaching since
1996. At present he is working as Associate
Professor. Achieved excellent experiences in
Research for 15 years in the area of Boundary
value problems and its application. Published more than 45
research papers in reputed journals. Four students awarded
Ph.D Degree and four students working for award of Ph.D.
Degree under their guidance.
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Volume: 03 Issue: 05 | May-2014, Available @ http://www.ijret.org
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