BNLearn:如何将高斯贝叶斯网络的估计参数与其条件结构合并?

时间:2019-04-24 09:59:57

标签: r bayesian bayesian-networks bnlearn

我使用iamb函数定义了高斯贝叶斯网络的结构,然后使用bn.fit估计了节点的系数。


图书馆

library(bnlearn)

数据

{  C       E       G       N       V       W
48.83   51.48   42.64   54.1    42.96   41.96
48.85   73.43   40.97   60.07   65.29   48.96
67.01   71.1    52.52   51.64   63.22   62.03
37.83   49.33   56.15   49.01   47.75   38.77
55.3    49.27   63.55   54.62   60.57   56.66
56.12   48.72   66.02   43.95   55.54   52.39}

代码

# Definition of mandatory and forbidden nodes - here the white list
wl = data.frame(from = c("E","G","V","W","N"), to = c("V", "V","W","C","C"))

# Definition of the constrained network
network <- iamb(Data, test = "cor", whitelist = wl)

# Estimation of the coefficients according to the structure of the network
est.para <- bn.fit(network, data = Data)

问题在于est.para是一个列表,而不是可以绘制的GBN,等等。我想知道如何合并网络和估计的参数吗? < / p>

1 个答案:

答案 0 :(得分:0)

如果要使网络图显示除连接之外的其他信息,可以使用strength.plot。按照您的示例:

library(Rgraphviz)

strength <- arc.strength(network, Data)
strength.plot(network, strength, shape = "ellipse")

如果绝对需要使用GBN est.para的参数结果,则可以使用graphviz.plot参数突出显示边缘和节点(可以使用edgeRenderInfo完成)和nodeRenderInfo)。仅作为示例,您可以使用参数选择边缘的宽度:

library(data.table) 

plot <- graphviz.plot(network, shape = "ellipse")

arc.sizes <- data.table(network$arcs)
arc.sizes[, edge.name := paste0(arc.sizes$from, "~", arc.sizes$to)]
arc.sizes[, param := abs(est.para[[to]]$coefficients[[from]]), by = .(from, to)]
arc.sizes[, lwd := 5*((param - min(param))/(max(param) - min(param)))]

lwd <- as.vector(arc.sizes$lwd)
names(lwd) <- arc.sizes$edge.name
edgeRenderInfo(plot) <- list(lwd = lwd)

renderGraph(plot)