Fig. 1. Conceptual framework showing the major components and relations of the social-ecological system represented in the Evoland model. The dashed arrows indicate flows of information. The solid arrows indicate changes to the landscape. The agent decision-making process, which is repeated annually for each parcel, is tantamount to stochastic sequential optimization of the landscape for societal goals and agent preferences. The process begins when the agent selects the subset of policies admissible on the current parcel, e.g., riparian policies for riparian parcels. Next, admissible policies are ranked on the basis of policy effectiveness ratings. One rating for each of the ecosystem health and economic values indicates the capacity of the policy to change the landscape on that metric. Two factors contribute to the highest rankings. One is the match between policy ratings and agent preferences. The other depends on the magnitude of the landscape deficiencies and the capacity of the policy to correct them; this factor is proportional to the magnitude of the deficiencies. Finally, one of these policies is chosen stochastically, with the highest ranking policy the most likely to be selected. A landscape evaluation provides feedback to the decision algorithm regarding deficiencies. Other change processes do not involve agent decision making directly, but do cause landscape changes that affect the landscape state.