discrete bayesian network
=========================

This is an example input file for a Bayesian network with discrete conditional probability distributions. The example is a small (5 node) graph modeling a student's performance. The graph skeleton data is also included, in the vertex set ("V") and the edge set ("E"). The graph itself is from Koller et al. 53.::

    {	
        "V": ["Letter", "Grade", "Intelligence", "SAT", "Difficulty"],
        "E": [["Intelligence", "Grade"],
            ["Difficulty", "Grade"],
            ["Intelligence", "SAT"],
            ["Grade", "Letter"]],
        "Vdata": {
            "Letter": {
                "ord": 4,
                "numoutcomes": 2,
                "vals": ["weak", "strong"],
                "parents": ["Grade"],
                "children": None,
                "cprob": {
                    "['A']": [.1, .9],
                    "['B']": [.4, .6],
                    "['C']": [.99, .01]
                }
            },
            
            "SAT": {
                "ord": 3,
                "numoutcomes": 2,
                "vals": ["lowscore", "highscore"],
                "parents": ["Intelligence"],
                "children": None,
                "cprob": {
                    "['low']": [.95, .05],
                    "['high']": [.2, .8]
                }
            },
            
            "Grade": {
                "ord": 2,
                "numoutcomes": 3,
                "vals": ["A", "B", "C"],
                "parents": ["Difficulty", "Intelligence"],
                "children": ["Letter"],
                "cprob": {
                    "['easy', 'low']": [.3, .4, .3],
                    "['easy', 'high']": [.9, .08, .02],
                    "['hard', 'low']": [.05, .25, .7],
                    "['hard', 'high']": [.5, .3, .2]
                }
            },
            
            "Intelligence": {
                "ord": 1,
                "numoutcomes": 2,
                "vals": ["low", "high"],
                "parents": None,
                "children": ["SAT", "Grade"],
                "cprob": [.7, .3]
            },
            
            "Difficulty": {
                "ord": 0,
                "numoutcomes": 2,
                "vals": ["easy", "hard"],
                "parents": None,
                "children": ["Grade"],
                "cprob":  [.6, .4]
            }
        }
    }