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When fairness prevails

first_imgPhilosophers and scientists have long puzzled over the origins of fairness. Work by a group of Harvard researchers offers some clues, with the discovery that uncertainty is critical in the concept’s development.Using computer simulations of evolution, researchers at Harvard’s Program for Evolutionary Dynamics (PED) — including Director Martin Nowak, scientist David Rand, and junior fellow Corina Tarnita — found that uncertainty is key to fairness. Hisashi Ohtsuki from the Graduate University for Advanced Studies in Kanagawa, Japan, also contributed to the study. Their work was described in a Jan. 21 paper in the Proceedings of the National Academy of Sciences.“A number of papers have studied the evolution of fairness over the years,” said Rand, who will begin an assistant professorship at Yale this summer. “Our novel contribution was to take the effects of randomness into account. What we found was that as we turned up the uncertainty in our simulations, it fundamentally changed the nature of the evolutionary dynamic. The result was that in a world that has a lot of uncertainty, it actually became optimal to be fair, and natural selection favored fairness.”To model fairness, Rand and colleagues used the Ultimatum Game, which involves two players bargaining over a pot of money. The first player proposes how the money should be split. If the second player accepts the offer, the money is split as proposed; if the offer is rejected, the game is over and neither player gets anything.“The reason this game is interesting is that if you assume everyone is rational and self-interested, the second player should accept any offer, because even if they’re getting only one dollar it’s still better than nothing,” Rand said. “The first player should anticipate that, and should make the minimum possible offer.”The game almost never works that way, however.Instead, Rand said, many people will reject offers they believe are unfair. Earlier studies have shown that as many as half of players will reject offers of 30 percent or less — meaning they are effectively paying to retaliate against the other player for making such a low offer, or to stop the other player from getting ahead.“The proximate psychological explanation for why people behave this way in the Ultimatum Game is that they have a preference for fairness, and they’re willing to pay to create equality,” Rand said. “The question we were trying to answer was: Why? Why did we come to have those preferences?”Rand and his colleagues built a series of computer players, each of which had a specific strategy describing how much they would offer, and how much they would accept. Each round, all the computer players played the game with one another. Then they updated their strategies in a process similar to genetic evolution.“You can think of it as though the players that earned higher payoffs attracted more imitators. Players sometimes choose to change their behavior, and when they do, they copy the strategies of players who were more successful,” Rand explained. “It could also represent actual genetic evolution, where players with [a] big payoff leave more offspring. Either way, higher payoff strategies tend to become more common in the population over time.”By observing which strategies become dominant over multiple generations, the researchers were able to track how the system evolved, and saw that fairness offered players an evolutionary advantage, but only when uncertainty was factored into the system.To test whether these results would play out in the real world, Rand and colleagues used the online labor market Amazon Mechanical Turk to recruit hundreds of volunteers from around the globe. After playing the Ultimatum Game, participants were asked how easy it was for people in their community to determine who is, and who isn’t, successful.“We found exactly what the model predicted, which, I think, wouldn’t have been at all obvious had we not done the modeling first,” Rand said. “What we found is a correlation — the more uncertainty there is about who is successful and who isn’t, the more fair people are in the Ultimatum Game.”Understanding why that is, however, is trickier.“Think about a world where nobody is offering anything — everyone is completely rational and self-interested,” Rand said. “If you introduce a fair person into a world like that, they will do poorly, because they will make generous offers, and people will accept them. Other people, however, will make low offers to that person, and they will be rejected. As a result the fair person will never have the chance to succeed.”The same is true of a rational person in a generally fair world. Their low offers will be rejected, resulting in a poor payoff.So what happens if you assume that successful strategies are always successful and unsuccessful strategies are always unsuccessful, as previous studies have?“If you’re in a selfish world, the population can never leave that state, because the fair person is always at a disadvantage,” he said. “If you rely on these kind of deterministic dynamics, that first fair person is always going to die out and fairness as a strategy will never spread.“Whereas in a world where there’s uncertainty, when someone experiments with a fair strategy in a world of selfish people, they will still get a bad payoff, but sometimes just by chance that fair strategy might become more common in the population,” he continued. “And once it becomes common enough, the momentum switches and it’s better to be fair than selfish. That’s how it becomes the favored behavior.”This work was funded by support from the John Templeton Foundation.last_img read more


Cricket News Ravichandran Ashwin’s similar injuries ‘unfortunate’: Virat Kohli

first_imgNew Delhi: Ravichandran Ashwin is in doubt for the Sydney Test against Australia after failing to recover from the left side strain which he sustained in the Adelaide Test. Although he was named in the 13-man squad for the final Test, India cricket team skipper Virat Kohli said his inclusion in the playing XI is ‘in doubt’ and admitted that all is not well with the Tamil Nadu offspinner. The Indian cricket team are currently leading the series 2-1 following their 137-run win in the Melbourne Test and are aiming to become the first Asian side ever to win a Test series Down Under. Speaking in the pre-match press conference ahead of the final Test, Kohli said the physio and trainer have spoken to him as to what is required.“It’s unfortunate that Ashwin has had two niggles quite similar in the last couple of away tours (England and now Australia). He, more than anyone else, will be focused to correct this. The physio and the trainer have spoken to him in terms of what’s required (from him) in order to get over that injury. He is very important for sure. In Test cricket, he is a vital part of this team and we want him to be 100 per cent fit and for a longer period so that he can contribute to us more in the Test format,” Kohli said.Read More | BCCI announces 13-man squad for SCG Test, call on Ashwin tomorrow Ashwin had sustained a left-side strain during the England series and he was less effective in the Southampton Test which India lost by 60 runs to lose the series as well. The offspinner was ruled out of The Oval Test and in Adelaide, he bowled 86 overs and did not allow Australia to score freely as India secured a 31-run win. However, Ashwin was ruled out of the Perth Test and has failed to make a recovery since.Read More | Not thought too much about losing series against India: Tim Paine“He (Ashwin) is very disappointed with the fact that he has not been able to recover in time, but the things have been laid out to him (as to) what needs to be done to get back to full fitness. Honestly, you can’t predict an injury. When it happens, you just manage and doing what you can to get over that injury,” Ashwin said.Vihari’s offspin a boost In Ashwin’s absence, the likes of Ravindra Jadeja and Hanuma Vihari have chipped in well. In Perth, Vihari provided the breakthrough with his handy offspin while Jadeja was the star in the Melbourne Test. Kohli said Vihari’s offbreaks have given the Indian cricket team a real comfort zone in the absence of Ashwin.“Ashwin’s absence does make you alter plans a little bit throughout the course of a series. But the fact that Hanuma Vihari has bowled beautifully whenever we have given him the ball makes us feel absolutely calm about Ashwin not being able to play. But, if you see the way Vihari has bowled he has looked like picking up a wicket whenever he comes to bowl. He’s pitching the ball in the right areas so we are looking at him as a solid bowling option right now. Especially in this Test because he has pace on the ball, he puts in the effort, he’s economical and that’s all you need from a guy who is coming in to bowl 10-15 overs in a day,” Kohli said.Kohli revealed that he had been plagued by back injuries ever since he entered the Indian cricket team in 2011 but added that certain routines have ensured he remained on top of his fitness in all three formats. During the Melbourne Test, he had suffered a back injury but he played through the Test match without witnessing any kind of discomfort.“I have been able to manage it because of the physical effort I have put in in the last few years. he physical part has definitely helped me massively in the last three years. I feel like I can switch formats easily. And I can be at the top of my energy levels or intensity levels that is required to play international cricket because I work really hard no my fitness. There are many factors involved: the diet, the sleep patterns and all these sort of things are very crucial,” Kohli said.India lead the four-match series 2-1 and a win or draw in Sydney will help them create history. For all the Latest Sports News News, Cricket News News, Download News Nation Android and iOS Mobile Apps.last_img read more