// ~->[DNET-1]->~ // File created by Norsys using Netica 1.06b on Mar 29, 1998 at 05:34:42. bnet Matheson90_Space_Mission { autoupdate = TRUE; comment = "A classic influence diagram used as an example of how to do \ value-of-information calculations. \n\ A decision is to be made whether to send a space mission to \ Mars or Venus, where the success of the mission is \ uncertain. \n\ Among other things, we find the value of perfect information \ on the reliablities of the launch subsystems and the \ descender subsystems, which can then be used to decide \ whether to do further testing. \n\ From Matheson, James E. (1990) \"Using influence diagrams to \ value information and control\", in Influence Diagrams, \ Belief Nets and Decision Analysis, R. M. Oliver and J. Q. \ Smith (eds.), John Wiley & Sons."; whenchanged = 891178277; visual V2 { defdispform = BELIEFBARS; nodelabeling = TITLE; nodefont = font {shape= "Arial"; size= 10;}; linkfont = font {shape= "Arial"; size= 9;}; commentfont = font {shape= "Arial"; size= 10;}; windowposn = (4, 9, 685, 441); resolution = 72; drawingbounds = (1152, 752); showpagebreaks = FALSE; usegrid = TRUE; gridspace = (6, 6); }; node Mars_Descender { kind = NATURE; discrete = TRUE; chance = CHANCE; states = (Success, Fail); parents = (); probs = // Success Fail (0.9230769, 0.07692307); visual V2 { center = (120, 54); height = 6; }; }; node Launch { kind = NATURE; discrete = TRUE; chance = CHANCE; states = (Success, Fail); parents = (); probs = // Success Fail (0.65, 0.35); visual V2 { center = (288, 54); height = 5; }; }; node Result_Mars { kind = NATURE; discrete = TRUE; chance = CHANCE; states = (Success, Fail); parents = (Launch, Mars_Descender); probs = // Success Fail // Launch Mars_Descender (((1, 0), // Success Success (0, 1)), // Success Fail ((0, 1), // Fail Success (0, 1))); // Fail Fail ; visual V2 { center = (216, 132); height = 1; }; }; node Venus_Descender { kind = NATURE; discrete = TRUE; chance = CHANCE; states = (Success, Fail); parents = (); probs = // Success Fail (0.9230769, 0.07692307); visual V2 { center = (462, 54); height = 4; }; }; node Result_Venus { kind = NATURE; discrete = TRUE; chance = CHANCE; states = (Success, Fail); parents = (Launch, Venus_Descender); probs = // Success Fail // Launch Venus_Descender (((1, 0), // Success Success (0, 1)), // Success Fail ((0, 1), // Fail Success (0, 1))); // Fail Fail ; visual V2 { center = (384, 132); height = 3; }; }; node Destination { kind = DECISION; discrete = TRUE; states = (Mars, Venus); parents = (); visual V2 { center = (114, 204); height = 7; }; }; node Result { kind = NATURE; discrete = TRUE; chance = CHANCE; states = (Success, Fail); parents = (Result_Mars, Result_Venus, Destination); probs = // Success Fail // Result_Mars Result_Venus Destination ((((1, 0), // Success Success Mars (1, 0)), // Success Success Venus ((1, 0), // Success Fail Mars (0, 1))), // Success Fail Venus (((0, 1), // Fail Success Mars (1, 0)), // Fail Success Venus ((0, 1), // Fail Fail Mars (0, 1)))); // Fail Fail Venus ; visual V2 { center = (306, 204); height = 2; }; }; node U { kind = UTILITY; discrete = FALSE; chance = DETERMIN; parents = (Destination, Result); functable = // Destination Result ((50, // Mars Success 10), // Mars Fail (100, // Venus Success -10)); // Venus Fail ; visual V2 { center = (210, 276); height = 8; }; }; node Destination1 { kind = DECISION; discrete = TRUE; states = (Mars, Venus); parents = (); visual V2 { center = (378, 288); height = 10; }; }; node Result1 { kind = NATURE; discrete = TRUE; chance = CHANCE; states = (Success, Fail); parents = (Destination1); probs = // Success Fail // Destination1 ((0.6, 0.4), // Mars (0.6, 0.4)); // Venus ; visual V2 { center = (552, 288); height = 9; }; }; node U1 { kind = UTILITY; discrete = FALSE; chance = DETERMIN; parents = (Destination1, Result1); functable = // Destination1 Result1 ((50, // Mars Success 10), // Mars Fail (100, // Venus Success -10)); // Venus Fail ; visual V2 { center = (462, 348); height = 11; }; }; };