Economic sciences/ 8.Mathematical methods in economics

 

Kostikina D., Kilincel T.

Saint-Petersburg State University, Russia

The application of the theory of cooperation games in research of Russian-Turkish processes of economic collaboration.

 

Investigation of the processes and principles of cooperation is interesting, relevant and important direction, which is caused by a number of reasons: in the current economic and geopolitical situation the trend of mutual approach between Russia and Turkey is growing. On the one hand it is due to crisis in the economy of Western Europe so Europe has to solve its own problems. The crisis on Cyprus is a striking example of attempts to tackle European economic problem at the expense of Russian business. On the other hand China as a principal partner of Russian Federation on the East cannot exhaust (satisfy) completely the interests of Russia in spite of its size. Successful promotion of the fundamental interests of Russia in the South European and the Middle East sector is impossible without consistency of acts with Turkey. Of course, Turkey cannot be considered as a simple and hassle-free partner, the presence of common interests does not mean the absence of conflicts and problems on both sides. From the above it should first be concluded that these problems and contradictions should not be left in the dark, they should be studied, including the use of economic-mathematical methods. In our opinion an adequate instrument of modeling process unfolding in the sphere of Russian-Turkish cooperation is the methodology of game theory as in the center of these problems is the issue of cooperative interaction.

The history of Russian-Turkish relations has more than 5 centuries, but most of this time between two countries were countless wars. Economic and investment cooperation between Russia and Turkey began in the 30s of the 20th century, but with the beginning of the Second World War it was interrupted and resumed in the 60s.

Among the most famous examples of cooperation between Russia and Turkey may be mentioned: the construction of APS “Akkuyu” in the province of Mersin (20 billion dollars), the construction of “Technostroyexport” in the consortium of the dam and hydroelectric power station “Deriner” (100 billion dollars), the construction of the gas pipeline “South Stream” in the Black Sea, which will connect Russia with the countries of Southern Europe, the construction of a car factory GAZ in the Turkish province of Sakarya with the participation of the Russian side in the face of “GAZ Group” company and the Turkish side in the face of “Mersa Otomotiv”.

Of course, these examples are characterized by complexity and versatility. Their appropriate study involves the use of quite a diverse and dissimilar economic models. In this case we will focus attention exactly on the cooperative effects inherent these models.

Lately, Russia and Turkey actively cooperate in the automotive industry. According to newspaper reports Russian automotive group "GAS" and the Turkish distributor "Merce Automotive" recently opened a car factory of GAZ commercial vehicles in the Turkish province of Sakarya, also Russian and Turkish partners will open a dealership and service network. GAZ cars will be sold not only at the Turkish market but also in Europe, North Africa and the Middle East.

Existing difficulties on political issue will not influence on the obvious successes of the economic cooperation between two countries, in spite of deep differences over the Syrian issue the cooperation between two countries continues to strengthen. Maybe this project will be the basis for long-term cooperation in the automobile industry between Russia and Turkey.

According to provisional data by the end of 2012 the company plans to produce 300 GAZ minibuses model "gazelle-business", and in 2013 production will increas to 2,500 cars with the prospect of increasing to 3700. There is an unoccupied niche of light commercial vehicles in Turkey and"GAZ Group" together with the Turkish company "Merce Automotive", which invested in the project 15 million euros, claim to it. The partners' plans are to win 7-10 percent of the local car market. Assembled in Turkey GAZ automobiles will be cheaper than the products of the competitors for 15-20%. The price will work out at 38,400 liras (about 21,300 U.S. dollars).

Until recently only 3 companies mostly produced vans in Turkey: Ford Otosan, which produces on average 19,371 cars per year, Karsan (2936) and Otokar (168). Since 2013 GAZ company has begun to produce in Turkey, which is also planning to produce vans initially in the amount of 2500. Given the fact that in 2012 it turned out that Ford had 86% of the whole  minibus market share in Turkey, for two other companies (Karsan and Otokar) would be profitable to unit with the new company GAZ if their total winnings for each company will be more than if the company had not entered into a coalition. At the simplest level for the situation of the cooperation of both sides in the project, which unites three participants, may be suggested the next game-theoretical cooperative model.

Part of the game theory, where players can form a coalition called the theory of cooperative (coalitional) games. We assume that this game is a game with transferable utility. Our cooperative game we denote by a pair (I, v), where the I-set of players, and v - the characteristic function, and any subset S of the set I are called coalitions of players. The characteristic function of a cooperative game is a function that each possible coalition S assigns to the utility (win) which the coalition can get.

In out case we get:

 – that means that the Otokar company produce by itself 168 cars per year and occupies 1% of the market.

 – characteristic function of a player Karsan.

 – characteristic function of a player GAZ.

         If the first and the second player join up their characteristic function is:

         The same for other integrations: ;

The characteristic function for 3 players:

         Thus, it appears that due to combining all three players can get 33% of the market.

Allocating a prize, which will be estimated at the number of vehicles manufactured by each company, the capacity constraints of the plants must be taken into account: Otokar no more than 1500, Karsan no more than 16 300, GAZ no more 3700.

The game is superadditive:

And convex: 

         The basic concept for the game theory is the concept of imputation. In cooperative game (I, v) imputation is a vector x = (x1, ..., xi, ..., xn) (n = | I |-the number of players), which satisfies the conditions:

·       - the condition of group rationality, i.e. imputation must completely distribute utility receives by combining all the players in the coalition.

·         - the condition of individual rationality, i.e. imputation should give the player as much as he can get, without entering into any of the coalitions, where  is the utility that must be given to player i.

 - the utility, that coalition S should receive:

If the vector x satisfies only the conditions of group rationality, it is called a pre-imputation or distribution.

The solution of a cooperative game should give us the answer to the question: what shares can the players count on in the win of the grand coalition v(I)? Reasonable solution to the cooperative game is to find the Shapley value. According to the Shapley value the share of the player i in the imputation is:

 where s=|S| - the number of players in coalition.

Imputation x dominates imputation y of the coalition S, if:

 

The first condition means that the imputation x is more profitable than the imputation y for all members of the coalition S, and the second condition means that the coalition S can actually provide it due to its win v(S).

Imputation x dominates y if there is an imputation of at least one coalition on which it occurs.

Core - is the set of undominated imputations in the game (I, v), it is denoted C(v).

It’s simple to show, that:

         Core is a set of imputations that cannot be objectively challenged by any of the coalitions. This solution is associated with two fundamental problems:

1. In certain situations, core can be very large, what makes the choice of preferred imputation of it ambiguous.

2. In some cases, core may be empty.

If the game is convex, the Shapley value always belongs to core, but if the game is superadditive and is not convex, the Shapley value cannot belong to core even if it is not empty.

Now we will show a geometric interpretation for the core in the considered game. It is possible because the game gets three players, and therefore imputations and pre-imputations are vectors in three-dimensional space. Then the condition of group rationality takes the form:

 

For this condition there is a plane in three-dimensional space, which intersects the axes at the points: (0,33;0;0), (0;0,33;0), (0;0;0,33).

Conditions of individual rationality of players:

         These inequalities "cut" from the plane the triangle, i.e. set of imputations in the game is a 3-simplex with vertices (0.33, 0, 0), (0, 0.33, 0), (0, 0, 0.33). Set of points on the plane are the pre-imputations in this game.

Also the constraints on the coalitions must be considered:

                                                                (1)

This means that the imputation belonging to core should not give in the coalition of the first and second players less than 0.15, or they had better not join up into the coalition of three players. For similar reasons:

                                                     (2)

                                                     (3)

 


000

Прямоугольная выноска: C-ядро

(0;0;0,33)

 

(0;0,33;0)

 

(0,33;0;0)

 
000000000000000251689984

 

 

 

 

 


D

 
00

 

 

 

 

 

 

 


Picture 1. Geometric characterization of the core.

The set of imputations satisfying (1), is "above" the plane , and the set of imputations that satisfy the condition (2) is above the plane         , for condition (3) - above the plane . The result of their intersection with the plane gives a figure marked by grey color. This figure is the locus of points that belong to the core of the game. This game model is one of those situations where the core is large enough. Thus, in this situation, to find a reasonable solution that satisfies all the constraints, it is sufficient to calculate the Shapley value: ; ;

Thus it turns out that when the first player joins to the grand coalition he gets 3% of the market, the second - 16%, and the third - 14%, and together they will take 33% of the market, therefore, the market share for Ford reduces and becomes 67% against 86%.

Also we can count the values in the points of extremum:

A=(0,05;0,13;0,15), B=(0,02;0,13;0,18), C=(0,01;0,14;0,18), D=(0,01;0,2;0,12), E=(0,02;0,2;0,11), F=(0,05;0,17;0,11)

It should be noted that this model uses a relative income of firms, i.e. we assume that the income linearly proportional to the market share and is assumed to be some constant: const • α, where α - market share. Therefore, in the calculation examples we directly the value of the market share.

Among the present-day works in which the problems of application of methods of game theory to solve the problems of economic collaboration are considered may be mentioned:

·       Konyukhovskiy P., “The application of stochastic cooperative games in studies of regularities in the realization of  large-scale investment projects”,  2012

·       Konyukhovskiy P., Malova A., Kylynchel T., “Comparative analysis of mobile telecoomunication sphere in Russian Federation and Turkish Republic using differential equations”, 2012

·       Konyukhovskiy P., Malova A.,”The application of methods of game theory in analysis of relations of collaboration between economic subjects”, 2012

·       Konyukhovskiy P., “The application of stochastic cooperative games to justify the investment projects”, 2012

These models are certainly quite abstract and simplistic, but they can increase the level of confidence in the research of future evolution patterns of Russian-Turkish economic relations.

Literature:

1.     Pecherskiy S., Belyaeva A., “Game theory for economists”, 2001

2.     Kannai Y., “The core and balancedness”, 1992

3.     Shapley L.S., “On balanced sets and cores”, 1967

4.     Konyukhovskiy P., “The application of stochastic cooperative games in studies of regularities in the realization of  large-scale investment projects”,  2012

5.     Konyukhovskiy P., Malova A., Kylynchel T., “Comparative analysis of mobile telecoomunication sphere in Russian Federation and Turkish Republic using differential equations”, 2012

6.     Konyukhovskiy P., Malova A.,”The application of methods of game theory in analysis of relations of collaboration between economic subjects”, 2012

7.     Konyukhovskiy P., “The application of stochastic cooperative games to justify the investment projects”, 2012

8.     The publication of the Chamber of Commerce and Industry

 http://www.tpp-inform.ru

9.     The internet-publication www.pandia.ru

10. The internet-publication of the radio station “The voice of Russia” http://rus.ruvr.ru

11. Automotive manufacturers association http://www.osd.org.tr