Game Theory: Making the the World Blind One High Beam at a Time
As shown in the “THE DRIVING THEORY”, the high-beam/low-beam scenario is a basic example of game theory in real life that demonstrates how making decisions with self-interest in mind can hurt both the decision makers and society. In this game, suppose there are two players, Driver 1 and Driver 2, each driving on the same highway at night in opposite directions (assume there is no median between them). Each player must pick one of two strategies: High Beam or Low Beam. If one player uses High Beam, while the other uses Low Beam, the one using High Beam has maximum visibility, while the one using Low Beam has none. If both players choose the same strategy, they both have some visibility, but visibility is higher when they both use Low Beam as opposed to the High Beam. We display this game in the payoff matrix below, where a higher value denotes a higher visibility. Note that he first value is Driver 1’s payoff while the second value is Driver 2’s payoff.
Studying this matrix, we can see that Driver 1’s dominant strategy, the strategy that gives him the highest payoff regardless of what strategy Driver 2 selects, is High Beam. The same also applies for Driver 2. As a result, in the Nash Equilibrium, both players will use High Beam. Notice that this is a case of the classic “Prisoner’s Dilemma” because the best-case scenario for the players (and society) is for both to use Low Beam to gain higher payoffs and therefore visibility, but players won’t select Low Beam because they know that if the other player selects High Beam, their payoff will be 0. Neither player is willing to take the risk of 0 payoff to get a higher payoff. In other words, each player acts with their own self-interest in mind to achieve an outcome in which they are worse off with low, albeit some, visibility. But how does this type of decision making affect the rest of society?
Daniel Knowles addresses this issue in his article about driving accidents in African countries. He notes that Kenya, in particular, has some of the most traffic deaths in the world relative to its population, a fact that is even more alarming considering the scarcity of cars in the country. Though he attributes some deaths to third-world problems like poor lighting and roads, Knowles believes that another main cause is driving through the dark with high beams on as a result of the game above. As we saw earlier, when two drivers are driving in the dark, they are both likely to use a high beam. Though this decision is in the best interest of each driver themselves, it is detrimental to society because both now have reduced visibility and will have trouble seeing other cars and pedestrians. According to this matrix, the best outcome for society would be for both drivers to use low beams to ensure they both have equal and increased visibility. This is an example of what economists (and Knowles) call a “globally inferior Nash Equilibrium.” In other words, everyone is expected to choose a decision based on their own self-interest, so you must too or your payoff will be 0. In the end, everyone is worse off. If everyone instead acted with society’s interest in mind, they would all receive higher payoffs and their choices would also benefit society. In the case of traffic deaths in Kenya, if all drivers used low beams, they would all have higher visibility, and be able to see other drivers and pedestrians, thereby ensuring safer travel for everyone, including themselves.
Sources:
[Kenya car crashes tell us truths about what makes a society work – or not] (http://www.afr.com/lifestyle/kenya-car-crashes-tell-us-truths-about-what-makes-a-society-work–or-not-20170823-gy26ke#ixzz4t5PBGaPD)
[THE DRIVING THEORY] (http://goaconference.org/the-driving-theory/)