Exemple #1
0
        public void CalculateNormativeFit(Context currentContext, Simulation simulation)
        {
            int numDimensions = currentContext.relevantCharacteristcs.Count;

            for (int c = 0; c < clusterMeans.Count; c++)
            {
                var clusterMean = clusterMeans[c];

                float bestDistance = float.MaxValue;

                foreach (var socialGroup in knowledgeBase)
                {
                    bool validGroup = true;

                    float distance = 0.0f;

                    for (int i = 0; i < numDimensions; i++)
                    {
                        float groupValue = 0.0f;
                        if (!socialGroup.characteristics.TryGetValue(currentContext.relevantCharacteristcs[i], out groupValue))
                        {
                            validGroup = false;
                            break;
                        }

                        float weight = currentContext.relevantCharacteristcs[i].weight;

                        float difference = (clusterMean.mean[i] - groupValue) * weight;
                        distance += difference * difference;
                    }

                    if (!validGroup)
                    {
                        continue;
                    }

                    distance = (float)Math.Sqrt((double)distance);

                    if (distance < bestDistance)
                    {
                        bestDistance             = distance;
                        clusterMean.matchedGroup = socialGroup;
                    }
                }

                // ad-hoc group
                if (bestDistance > simulation.normativeMatchDistance * currentContext.GetMaxDistance())
                {
                    numAdhocGroups++;

                    SocialGroup adhocGroup = new SocialGroup();
                    adhocGroup.isAdHoc = true;

                    adhocGroup.characteristics = new Dictionary <Characteristic, float>();

                    adhocGroup.name = "Group " + numAdhocGroups;

                    for (int i = 0; i < numDimensions; i++)
                    {
                        adhocGroup.characteristics.Add(currentContext.relevantCharacteristcs[i], clusterMean.mean[i]);
                    }

                    adhocGroup.CalculateAccessibility(this);

                    knowledgeBase.Add(adhocGroup);

                    clusterMean.matchedGroup = adhocGroup;
                }

                clusterMeans[c] = clusterMean;
            }
        }
Exemple #2
0
        /*
         * public void NormalizeAccessibility()
         * {
         *  float totalAccessibility = 0.0f;
         *
         *  foreach (var socialGroup in knowledgeBase)
         *  {
         *      totalAccessibility += socialGroup.accessibility;
         *  }
         *
         *  if (totalAccessibility == 0.0f)
         *  {
         *      foreach (var socialGroup in knowledgeBase)
         *      {
         *          socialGroup.accessibility = 1.0f / knowledgeBase.Count;
         *      }
         *  }
         *  else
         *  {
         *      foreach (var socialGroup in knowledgeBase)
         *      {
         *          socialGroup.accessibility /= totalAccessibility;
         *      }
         *  }
         * }*/

        public void CalculateComparativeFit(Context currentContext, Simulation simulation)
        {
            salience = minimalSalienceThreshold;

            foreach (var socialGroup in knowledgeBase)
            {
                float groupComparativeFit;

                int numDimensions = currentContext.relevantCharacteristcs.Count;

                int selfCluster = GetSelfCluster();

                float meanDistance = 0.0f, meanDispersion = 0.0f;

                bool validGroup = true;

                for (int c = 0; c < clusterMeans.Count; c++)
                {
                    if (c == selfCluster)
                    {
                        continue;
                    }

                    var clusterMean = clusterMeans[c];

                    float distance = 0.0f;

                    for (int i = 0; i < numDimensions; i++)
                    {
                        // Comparative distance with visible groups or matched groups
                        float groupValue = 0.0f, selfGroupValue = 0.0f;
                        clusterMean.matchedGroup.characteristics.TryGetValue(currentContext.relevantCharacteristcs[i], out groupValue);

                        if (!socialGroup.characteristics.TryGetValue(currentContext.relevantCharacteristcs[i], out selfGroupValue))
                        {
                            validGroup = false;
                            break;
                        }

                        float weight = currentContext.relevantCharacteristcs[i].weight;

                        float difference = (groupValue - selfGroupValue) * weight;
                        distance += difference * difference;
                    }

                    if (!validGroup)
                    {
                        break;
                    }

                    meanDistance += (float)Math.Sqrt((double)distance) / currentContext.GetMaxDistance();

                    meanDispersion += clusterMean.dispersion;
                }

                if (!validGroup)
                {
                    continue;
                }

                if (clusterMeans.Count > 1)
                {
                    meanDistance   /= clusterMeans.Count - 1;
                    meanDispersion /= clusterMeans.Count - 1;

                    groupComparativeFit = simulation.comparativeFitAlfa * meanDistance + (1.0f - simulation.comparativeFitAlfa) *
                                          (simulation.comparativeFitBeta * (1.0f - clusterMeans[selfCluster].dispersion) + (1.0f - simulation.comparativeFitBeta) * meanDispersion);
                }
                else
                {
                    meanDistance = 0.0f;

                    groupComparativeFit = 0.0f;
                }

                float groupSalience = groupComparativeFit * socialGroup.accessibility;

                socialGroup.salience = groupSalience;

                if (groupSalience > salience)
                {
                    selfGroup      = socialGroup;
                    salience       = groupSalience;
                    comparativeFit = groupComparativeFit;

                    groupMeanDistance = meanDistance;
                }
            }
        }