J. Andreoni, Cooperation in public-goods experiments: kindness or confusion? The American Economic Review, pp.891-904, 1995.

J. Andreoni and R. Petrie, Public goods experiments without confidentiality: a glimpse into fund-raising, Journal of Public Economics, vol.88, issue.7-8, pp.1605-1623, 2004.

S. Aron and L. Passera, Les sociétés animales: évolution de la coopération et organisation sociale, 2009.

G. S. Becker, A theory of social interactions, Journal of Political Economy, vol.82, issue.6, pp.1063-1093, 1974.

M. Belot, R. Duch, and L. Miller, A comprehensive comparison of students and non-students in classic experimental games, Journal of Economic Behavior & Organization, vol.113, pp.26-33, 2015.

O. Bochet, T. Page, and L. Putterman, Communication and punishment in voluntary contribution experiments, Journal of Economic Behavior & Organization, vol.60, issue.1, pp.11-26, 2006.

O. Bochet and L. Putterman, Not just babble: Opening the black box of communication in a voluntary contribution experiment, European Economic Review, vol.53, issue.3, pp.309-326, 2009.

G. E. Bolton and A. Ockenfels, ERC: A theory of equity, reciprocity, and competition, The American Economic Review, vol.90, issue.1, pp.166-193, 2000.

E. Buckley and R. Croson, Income and wealth heterogeneity in the voluntary provision of linear public goods, Journal of Public Economics, vol.90, issue.4-5, pp.935-955, 2006.

N. Nikiforakis, Punishment and counter-punishment in public good games: Can we really govern ourselves, Journal of Public Economics, vol.92, issue.1-2, pp.91-112, 2008.

N. Nikiforakis, Feedback, punishment and cooperation in public good experiments, Games and Economic Behavior, vol.68, issue.2, pp.689-702, 2010.

N. Nikiforakis and H. Normann, A comparative statics analysis of punishment in public-good experiments, Experimental Economics, vol.11, issue.4, pp.358-369, 2008.

N. Nikiforakis, C. N. Noussair, and T. Wilkening, Normative conflict and feuds: The limits of self-enforcement, Journal of Public Economics, vol.96, issue.9, pp.797-807, 2012.

C. Noussair, Trends in academic publishing in experimental economics, Keynote lecture at the Journal of Economic Surveys Online Conference "Communications with Economists: Current and Future Trends" on November, vol.16, p.2011, 2011.

M. Olson, Logic of collective action: Public goods and the theory of groups, 1965.

E. Ostrom, Governing the commons, 1990.

E. Ostrom, J. Walker, and R. Gardner, Covenants with and without a sword: Self-governance is possible, American Political Science Review, vol.86, issue.2, pp.404-417, 1992.

T. R. Palfrey and J. E. Prisbrey, Anomalous behavior in public goods experiments: How much and why? The American Economic Review, pp.829-846, 1997.

M. Rabin, Incorporating fairness into game theory and economics, The American Economic Review, pp.1281-1302, 1993.

D. G. Rand, A. Dreber, T. Ellingsen, D. Fudenberg, and M. A. Nowak, Positive interactions promote public cooperation, Science, vol.325, issue.5945, pp.1272-1275, 2009.

A. S. Samek and R. M. Sheremeta, Recognizing contributors: an experiment on public goods, Experimental Economics, vol.17, issue.4, pp.673-690, 2014.

V. L. Smith, An experimental study of competitive market behavior, Journal of Political Economy, vol.70, issue.2, pp.111-137, 1962.

M. Sutter, S. Haigner, and M. G. Kocher, Choosing the carrot or the stick? endogenous institutional choice in social dilemma situations, The Review of Economic Studies, vol.77, issue.4, pp.1540-1566, 2010.

J. M. Walker and M. A. Halloran, Rewards and sanctions and the provision of public goods in one-shot settings, Experimental Economics, vol.7, issue.3, pp.235-247, 2004.

J. Zelmer, Linear public goods experiments: A meta-analysis, Experimental Economics, vol.6, issue.3, pp.299-310, 2003.

O. Kim and M. Walker, The free rider problem: Experimental evidence, Public Choice, vol.43, issue.1, pp.3-24, 1984.

M. Krawczyk and F. L. Lec, Give me a chance! an experiment in social decision under risk, Experimental Economics, vol.13, issue.4, pp.500-511, 2010.
URL : https://hal.archives-ouvertes.fr/hal-00675500

M. Krawczyk and F. L. Lec, Dictating the risk: Experimental evidence on giving in risky environments: Comment, The American Economic Review, vol.106, issue.3, pp.836-839, 2016.

M. W. Krawczyk, A model of procedural and distributive fairness, Theory and Decision, vol.70, issue.1, pp.111-128, 2011.

J. Ledyard, Public goods: A survey of experimental research. Handbook of Experimental Economics, pp.111-194, 1995.

M. V. Levati and A. Morone, Voluntary contributions with risky and uncertain marginal returns: the importance of the parameter values, Journal of Public Economic Theory, vol.15, issue.5, pp.736-744, 2013.

M. V. Levati, A. Morone, and A. Fiore, Voluntary contributions with imperfect information: An experimental study, Public Choice, vol.138, issue.1-2, pp.199-216, 2009.

L. Lévy-garboua, C. Montmarquette, J. Vaksmann, and M. C. Villeval, Voluntary contributions to a mutual insurance pool, Journal of Public Economic Theory, vol.19, issue.1, pp.198-218, 2017.

D. K. Marcus, V. Zeigler-hill, S. H. Mercer, and A. L. Norris, The psychology of spite and the measurement of spitefulness, Psychological Assessment, vol.26, issue.2, p.563, 2014.

R. O. Murphy, K. A. Ackermann, and M. Handgraaf, Measuring social value orientation, Judgment and Decision Making, vol.6, issue.8, pp.771-781, 2011.

T. Neugebauer, J. Perote, U. Schmidt, and M. Loos, Selfish-biased conditional cooperation: On the decline of contributions in repeated public goods experiments, Journal of Economic Psychology, vol.30, issue.1, pp.52-60, 2009.

M. Rabin, Incorporating fairness into game theory and economics, The American Economic Review, pp.1281-1302, 1993.

M. Rabin, A perspective on psychology and economics, European Economic Review, vol.46, issue.4, pp.657-685, 2002.

K. Saito, Social preferences under risk: Equality of opportunity versus equality of outcome, The American Economic Review, vol.103, issue.7, pp.3084-3101, 2013.

B. Stoddard, Uncertainty in payoff-equivalent appropriation and provision games. Working Papers in Economics, 2013.

B. V. Stoddard, Probabilistic production of a public good, Economics Bulletin, vol.34, issue.4, pp.2427-2442, 2014.

J. Stoop, C. Noussair, and D. Van-soest, From the lab to the field: Cooperation among fishermen, Journal of Political Economy, vol.120, issue.6, pp.1027-1056, 2012.

S. T. Trautmann, A tractable model of process fairness under risk, Journal of Economic Psychology, vol.30, issue.5, pp.803-813, 2009.

S. Vesely and E. Wengström, Risk and Cooperation: Experimental Evidence from Stochastic Public Good Games, Working Papers in Economics, issue.3, 2017.

J. Weimann, Questionnaire: 1. How many group members do you have?, Journal of Public Economics, vol.54, issue.2, pp.185-200, 1994.

, After the random draw, every group member will for sure receive the same proportion, p, of the project?

J. Bibliography-andreoni, Impure altruism and donations to public goods: A theory of warmglow giving, The Economic Journal, vol.100, issue.401, pp.464-477, 1990.

J. Andreoni, Cooperation in public-goods experiments: kindness or confusion? The American Economic Review, pp.891-904, 1995.

A. Angelovski, T. Neugebauer, and M. Servátka, Can rank-order competition resolve the free-rider problem in the voluntary provision of impure public goods? experimental evidence, Dipartimento di Economia e Finanza, 2017.

O. Bock, I. Baetge, and A. Nicklisch, hroot: Hamburg registration and organization online tool, European Economic Review, vol.71, pp.117-120, 2014.

G. E. Bolton and A. Ockenfels, ERC: A theory of equity, reciprocity, and competition, The American Economic Review, vol.90, issue.1, pp.166-193, 2000.

G. Bornstein and I. Erev, The enhancing effect of intergroup competition on group performance, International Journal of Conflict Management, vol.5, issue.3, pp.271-283, 1994.

G. Bornstein and A. Rapoport, Intergroup competition for the provision of step-level public goods: Effects of preplay communication, European Journal of Social Psychology, vol.18, issue.2, pp.125-142, 1988.

G. Bornstein, A. Rapoport, L. Kerpel, and T. Katz, Within-and between-group communication in intergroup competition for public goods, Journal of Experimental Social Psychology, vol.25, issue.5, pp.422-436, 1989.

E. Buckley and R. Croson, Income and wealth heterogeneity in the voluntary provision of linear public goods, Journal of Public Economics, vol.90, issue.4-5, pp.935-955, 2006.

C. Bull, A. Schotter, and K. Weigelt, Tournaments and piece rates: An experimental study, Journal of Political Economy, vol.95, issue.1, pp.1-33, 1987.

M. N. Burton-chellew, A. Ross-gillespie, and S. A. West, Cooperation in humans: competition between groups and proximate emotions, Evolution and Human Behavior, vol.31, issue.2, pp.104-108, 2010.

S. Cabrera, E. Fatás, J. A. Lacomba, and T. Neugebauer, Splitting leagues: promotion and demotion in contribution-based regrouping experiments, Experimental Economics, vol.16, issue.3, pp.426-441, 2013.

J. C. Cárdenas and C. Mantilla, Between-group competition, intra-group cooperation and relative performance, Frontiers in Behavioral Neuroscience, vol.9, p.33, 2015.

A. Chaudhuri, Sustaining cooperation in laboratory public goods experiments: a selective survey of the literature, Experimental Economics, vol.14, issue.1, pp.47-83, 2011.

A. Colasante, A. García-gallego, N. Georgantzis, A. Morone, and T. Temerario, Intragroup competition in public good games: The role of relative performance incentives and risk attitudes, Journal of Public Economic Theory, 2019.

L. Corazzini, M. Faravelli, and L. Stanca, A prize to give for: An experiment on public good funding mechanisms, The Economic Journal, vol.120, issue.547, pp.944-967, 2010.

R. Croson, E. Fatas, T. Neugebauer, and A. J. Morales, Excludability: A laboratory study on forced ranking in team production, Journal of Economic Behavior & Organization, vol.114, pp.13-26, 2015.

R. T. Croson, Feedback in voluntary contribution mechanisms: an experiment in team production, pp.85-97, 2001.

R. M. Dawes, J. M. Orbell, R. T. Simmons, A. J. Van-de, and . Kragt, Organizing groups for collective action, American Political Science Review, vol.80, issue.4, pp.1171-1185, 1986.

E. Dechenaux, D. Kovenock, and R. M. Sheremeta, A survey of experimental research on contests, all-pay auctions and tournaments, Experimental Economics, vol.18, issue.4, pp.609-669, 2015.

D. L. Dickinson and R. M. Isaac, Absolute and relative rewards for individuals in team production, Managerial and Decision Economics, pp.299-310, 1998.

I. Erev, G. Bornstein, and R. Galili, Constructive intergroup competition as a solution to the free rider problem: A field experiment, Journal of Experimental Social Psychology, vol.29, pp.463-463, 1993.

M. Faravelli and L. Stanca, Single versus multiple-prize all-pay auctions to finance public goods: An experimental analysis, Journal of Economic Behavior & Organization, vol.81, issue.2, pp.677-688, 2012.

M. Faravelli and L. Stanca, Economic incentives and social preferences: Causal evidence of non-separability, Journal of Economic Behavior & Organization, vol.108, pp.273-289, 2014.

U. Fischbacher, z-tree: Zurich toolbox for ready-made economic experiments, Experimental Economics, vol.10, issue.2, pp.171-178, 2007.

U. Fischbacher, S. Schudy, and S. Teyssier, Heterogeneous reactions to heterogeneity in returns from public goods, Social Choice and Welfare, vol.43, issue.1, pp.195-217, 2014.
URL : https://hal.archives-ouvertes.fr/hal-02076872

J. K. Goeree, E. Maasland, S. Onderstal, and J. L. Turner, How (not) to raise money, Journal of Political Economy, vol.113, issue.4, pp.897-918, 2005.

A. Gunnthorsdottir and A. Rapoport, Embedding social dilemmas in intergroup competition reduces free-riding, Organizational Behavior and Human Decision Processes, vol.101, issue.2, pp.184-199, 2006.

B. Irlenbusch and G. K. Ruchala, Relative rewards within team-based compensation, Labour Economics, vol.15, issue.2, pp.141-167, 2008.

E. P. Lazear and S. Rosen, Rank-order tournaments as optimum labor contracts, Journal of Political Economy, vol.89, issue.5, pp.841-864, 1981.

T. Markussen, E. Reuben, and J. Tyran, Competition, cooperation and collective choice, The Economic Journal, vol.124, issue.574, 2014.

J. Morgan, Financing public goods by means of lotteries, The Review of Economic Studies, vol.67, issue.4, pp.761-784, 2000.

J. Morgan and M. Sefton, Funding public goods with lotteries: experimental evidence, The Review of Economic Studies, vol.67, issue.4, pp.785-810, 2000.

M. Niederle and L. Vesterlund, Do women shy away from competition? do men compete too much?, The Quarterly Journal of Economics, vol.122, issue.3, pp.1067-1101, 2007.

N. Nikiforakis, Feedback, punishment and cooperation in public good experiments, Games and Economic Behavior, vol.68, issue.2, pp.689-702, 2010.

M. Olson, Logic of collective action: Public goods and the theory of groups, 1965.

M. Puurtinen and T. Mappes, Between-group competition and human cooperation, Proceedings of the Royal Society of London B: Biological Sciences, vol.276, pp.355-360, 1655.

A. Rapoport and G. Bornstein, Intergroup competition for the provision of binary public goods, Psychological Review, vol.94, issue.3, p.291, 1987.

A. Rapoport, G. Bornstein, and I. Erev, Intergroup competition for public goods: Effects of unequal resources and relative group size, Journal of Personality and Social Psychology, vol.56, issue.5, p.748, 1989.

E. Reuben and J. Tyran, Everyone is a winner: Promoting cooperation through all-can-win intergroup competition, European Journal of Political Economy, vol.26, issue.1, pp.25-35, 2010.

J. Sell and R. K. Wilson, Levels of information and contributions to public goods, Social Forces, vol.70, issue.1, pp.107-124, 1991.

J. H. Tan and F. Bolle, Team competition and the public goods game, Economics Letters, vol.96, issue.1, pp.133-139, 2007.

V. Théroude and A. Zylbersztejn, Cooperation in a risky world, Journal of Public Economic Theory, 2019.

J. Weimann, Individual behaviour in a free riding experiment, Journal of Public Economics, vol.54, issue.2, pp.185-200, 1994.

, In model M2, I compare the sum of contributions in SP-ROT and in SP-CTL. I reject the null assumption of equality in sum of contributions in SP-ROT and SP-CTL (one-tailed t-test, p-value = 0.075), Contributions are higher in SP-ROT than in SP-CTL

, Results indicate that inequalities are higher in SP-ROT (t-test, p-value = 0.014) and in SP-CTL (t-test, p-value < 0.001) than in NP-ROT. Moreover, a test of Student indicates that inequalities are higher in MP-CTL than in MP-ROT (p-value = 0.005), are higher in SP-ROT than in MP-ROT (p-value = 0.002), and are higher in SP-CTL than in MP-ROT(0.001). Inequalities are higher (weakly significant, SP-ROT and in SP-CTL than in MP-CTL, pp.p-value

, Among these 17 goals, the ecological issue (related to Goal 13, 14 and 15) and the peace issue (related to Goal 16) are central. 20 The United Nations Organization encourages countries and citizen to cooperate to change people's behaviour

A. Bibliography-alesina, R. Baqir, and W. Easterly, Public goods and ethnic divisions, The Quarterly Journal of Economics, vol.114, issue.4, pp.1243-1284, 1999.

A. Alesina and E. L. Ferrara, Participation in heterogeneous communities, The Quarterly Journal of Economics, vol.115, issue.3, pp.847-904, 2000.

Y. Algan, C. Hémet, and D. D. Laitin, The social effects of ethnic diversity at the local level: A natural experiment with exogenous residential allocation, Journal of Political Economy, vol.124, issue.3, pp.696-733, 2016.
URL : https://hal.archives-ouvertes.fr/halshs-00843173

E. Miguel, Tribe or nation? nation building and public goods in Kenya versus Tanzania, World Politics, vol.56, issue.3, pp.327-362, 2004.

E. Miguel and M. K. Gugerty, Ethnic diversity, social sanctions, and public goods in Kenya, Journal of Public Economics, vol.89, pp.2325-2368, 2005.