A graphical programming interface for use in developing computer programs providing computational decision-making capabilities. The interface uses a structure of graphically displayed positions, arguments and linkages to enable the development of computational decision making programs. The positions are primarily characterized by position values that may represent outputs although they may have a variety of other function features such as thresholds. The arguments are characterized by argument values that may represent inputs. The arguments are associated with particular positions and the values of the arguments associated with a given position are combined to determine the value of that position. The linkages extend between different positions and arguments and define different types of functional relationships between them. Programs are developed through the creation and manipulation of the graphical items of the interface using visually oriented processes such as drop down windows and drag and drop techniques.