Only abstract. Paper copies of master’s theses are listed in the Helka database (http://www.helsinki.fi/helka). Electronic copies of master’s theses are either available as open access or only on thesis terminals in the Helsinki University Library.Vain tiivistelmä. Sidottujen gradujen saatavuuden voit tarkistaa Helka-tietokannasta (http://www.helsinki.fi/helka). Digitaaliset gradut voivat olla luettavissa avoimesti verkossa tai rajoitetusti kirjaston opinnäytekioskeilla.Endast sammandrag. Inbundna avhandlingar kan sökas i Helka-databasen (http://www.helsinki.fi/helka). Elektroniska kopior av avhandlingar finns antingen öppet på nätet eller endast tillgängliga i bibliotekets avhandlingsterminaler.This thesis studies the evolution of conditional cooperation in a population where social norms are present. The model of Spichtig and Traxler (2007) is based in a public good setting where the members can choose to cooperate, contribute to the public good and adhere to the social norm or free-ride, not contribute towards the public good and thus break the social norm. Norm breaking sanctions imposed on any individual who chooses to behave in the latter manner. The exact degree of these norm sanctions on an individual's utility is determined by her individual norm sensitivity level, due to which some agents with a high norm sensitivity experience a higher utility loss from the norm sanctions in comparison with agents a lower degree of norm sensitivity. The model predicts for the population to evolve towards two equilibrium states which are characterised by a differing fraction of free-riders of the entire population. Two distinct models on learning are used to analyse further the learning mechanisms that might take place in such a population on an individual level. The model of Ellison and Fudenberg (1993) and the model of Banerjee and Fudenberg (2004) are similar in that they study a learning process of an individual in terms of new technology adoption. The former concentrates on horizontal learning which takes place within one generation and is based on mere observational clues whereas the latter analyses vertical learning taking place between generations and is based on more comlex word-of-mouth clues that are exchanged between members in the population and new entrants. Both of these models thereby us external clues as the means of learning of agents but differ in terms of what kind of learning is studied, intra-generational or inter-generational. The circumstances in and assumptions under which learning takes place in these two models are found to fit the model of the evolution of cooperation rather well and they could predict the learning mechanisms of this model in an individual level rather well
