2.1. Problem Description
Because enterprises, universities, research institutes, and other organizations are in the process of cooperation, their respective information strategies are not exactly the same, and in the whole process of cooperation, different groups will adopt different strategies according to the actual situation. Universities share innovation information with enterprises, but enterprises do not share innovation information with universities. Of course, research institutes share information just like universities do. It is important to emphasize that innovation information will not be shared between universities and research institutes. The university’s strategy is to share information and not to share information, and the institute will adopt the same strategy. When universities adopt information-sharing strategies, research institutes may adopt information-sharing strategies or non-information-sharing strategies. The different strategies adopted by the research are based on the changes in the strategies of universities and enterprises. To sum up, we can see that the strategies of universities, enterprises, and research institutes have the characteristics of an evolutionary game.
The industry–university–research innovation alliance consists of three organizations: enterprises, universities, and research institutes. Enterprises are the core organizations of the alliance, connecting universities and research institutes as connection points. There are information differences among alliance groups. The core organizations of the alliance are enterprises, which share information with universities and research institutes, respectively. Vertical cooperation and trust exist among innovation alliance groups. As downstream enterprises, universities and research institutes do not share information but have horizontal cooperation trust, as shown in
Figure 1. The alliance group has only two action strategies: sharing information and not sharing information. Under the influence of subjective and objective factors, the final action strategy of the enterprise in the innovation alliance can be obtained after many dynamic repeated games.
2.3. Evolutionary Game Analysis of an Alliance Group under a Vertical Cooperative Trust
The benefits of each group in the industry–university–research innovation alliance are composed of direct benefits, collaborative benefits, and sharing costs. Among them, the direct benefit is the product of the information-sharing amount, information unit value coefficient, information absorption capacity, and information absorption willingness. In contrast, the synergistic benefit is the product of the synergistic benefit coefficient, income distribution coefficient, and the total information-sharing amount. Based on this, the innovative information-sharing benefits of each group in the alliance can be obtained, as shown in
Table 1.
Enterprises make information-sharing decisions with universities and research institutes, respectively. Under a vertical cooperative trust, the cooperative relationship between the two does not affect the other. Therefore, the game between enterprises and universities is analyzed as an example.
Suppose that the income from information sharing in colleges and universities is
, the benefits of not sharing information are
, and the expected revenue is
. According to the payoff matrix in
Table 1, the payoff of colleges and universities choosing to share information under a vertical cooperation trust is shown in Equation (1):
The benefits of universities choosing not to share information are shown in Equation (2):
The expected income of colleges and universities is shown in Equation (3):
Thus, the replication dynamic equation is shown in Equation (4):
Similarly, the replication dynamic equation of enterprises’ innovation information-sharing strategies in the innovation alliance can be obtained using:
To simplify the expression, set
If Equations (4) and (5) are set to 0, respectively, then the local equilibrium point can be obtained as
and
. Where
. By taking partial derivatives of Equations (4) and (5), the Jacobian matrix of the game between the enterprise and the university can be obtained:
The following can be obtained using:
Then, the determinant and trace of the matrix (6) are, respectively,
Then, by putting the local equilibrium point into the above two equations, the local stability analysis results of the game can be obtained, as shown in
Table 2 below.
According to the relevant knowledge of evolutionary game theory, when
and
are true, the stable strategy of an evolutionary game is the same as the local equilibrium point. It can be seen from
Table 2 that determining the positive and negative of the determinant and trace corresponding to each equilibrium point is transformed into analyzing the value order of
and
, and
and
. The value order results are shown in
Table 3. Here “+” means positive sign, “−” means negative sign, and “/” means uncertain sign; “ESS” stands for evolutionary stable strategy.
Scenario 1: If , the evolutionary stability points are (0, 0) and (1, 1). In this scenario, both enterprises and universities can benefit from sharing innovation information, and the final evolutionary result among innovation alliance groups is sharing or not sharing.
Scenario 2: If , the evolutionary stability point is (0, 0). In this scenario, the profits from sharing innovation information can compensate for the cost, while universities cannot. Therefore, universities do not share information, and the final evolutionary result between innovation alliance groups is no sharing.
Scenario 3: If , the evolutionary stability point is (0, 0). In this scenario, the benefits obtained by colleges and universities from sharing information are greater than their sharing costs, while the benefits of enterprises cannot compensate for their costs. Therefore, enterprises do not share information, and the final sharing strategy among innovation alliance groups is no sharing.
Scenario 4: If , the evolutionary stability point is (0, 0). In this scenario, the benefits obtained from information sharing between enterprises and universities cannot compensate for their sharing costs, so the final stability strategy among innovation alliance groups is no sharing.
From the above analysis, it can be seen that whether the sharing strategy among innovation alliance groups can achieve stable sharing depends on whether the enterprises themselves can benefit from information sharing. The final evolutionary result has nothing to do with the income gap among innovation alliance groups. The above is the analysis of sharing strategies between enterprises and universities, similar to that between enterprises and scientific research institutes, which will not be analyzed separately here.
2.4. Evolutionary Game Analysis under a Horizontal Cooperation Trust
Since horizontal cooperation trust occurs in enterprises at the same level of the industry–university–research innovation alliance, that is, between universities and research institutes, the utility of enterprises remains unchanged, and the utility of universities and research institutes influences each other. Assume that the trust coefficient of horizontal cooperation is and that other assumptions are the same as those under a vertical cooperation trust.
When there is a horizontal cooperation trust between universities and research institutes, the set
represents the university’s income from sharing information, the income from not sharing information, and the average income of the university, respectively. As shown in
Table 1, the income from choosing to share information under a horizontal cooperation trust is
The revenue of the university from not sharing information is
The expected revenue of the university is
To simplify the formula, set
Thus, the replication dynamic equation of the strategy of sharing innovative information among universities in the alliance can be obtained using:
Similarly, the replication dynamic equation for studying the strategy of sharing innovative information in the alliance can be obtained using:
The replication dynamic equation of the strategy of sharing innovation information of enterprises in the alliance can be obtained using:
Respectively to enterprises, universities, and research institutes, the replicated dynamic equation is equal to zero, and available local equilibrium (0, 0), (0, 1), (0, 0), (0, 1, 1), (0, 1), (1, 1), (1, 0), (1, 1, 1), and
. Where the value of
and
is equal to the value under vertical fairness.
The Jacobian matrix can be obtained by taking the partial derivatives for
x,
y, and
z of the above replicated dynamic equations
, respectively,
In Equation (15), there is
If the local stable point is substituted into the Jacobian matrix, the other elements of the matrix except the main diagonal are equal to 0, where
are the three eigenvalues of the Jacobian matrix, respectively. The values of eigenvalues
in each equilibrium point of the game are shown in
Table 4.
Firstly, at the equilibrium point (1, 0, 0), since
always holds, the point (1, 0, 0) is not an evolutionary stable point. Secondly, if
,
is true, then at the equilibrium point (0, 1, 1), the eigenvalues
are greater than or equal to 0, so the equilibrium point (0, 1, 1) is not an evolutionary stable point. Finally, for other equilibrium points, the values of eigenvalues
at other points are positive or negative, as shown in
Table 5.
Scenario 1: If , , , , , then (1, 0, 1) is the stable point of the evolutionary game, that is, when the enterprises in the alliance obtain more income after sharing innovation information than their cost, and the research institutes obtain more income after sharing innovation information than the universities and the sharing cost is lower, the final evolutionary result is that the enterprises share information with the research institutes and the universities do not share information.
Scenario 2: If , , , , , , then (1, 1, 0) is the stable point of the evolutionary game, that is, when the benefits of innovation information shared by enterprises in the alliance are greater than their costs, when the benefits of information sharing by enterprises are higher than their costs, and the sharing benefits of universities are higher than and the sharing costs are lower than those of scientific research institutes, the final evolutionary result is information sharing between enterprises and universities. Scientific research institutes do not share information.
Scenario 3: If , , , , , , then (1, 1, 1) is the evolutional stable point, that is, when the enterprise’s income from information sharing is higher than its cost, and under the influence of a horizontal cooperation trust, universities and research institutes think that their profit is higher, and the alliance group will eventually choose to share information.
Scenario 4: If , the point (0, 0, 0) is the evolutionally stable point. Under the influence of a horizontal cooperation trust, when universities and research institutes think that their sharing cost is higher than that of the other party, the final sharing strategy of the alliance group is not to share.