###Brown-Mood中位數(shù)檢驗(yàn)（精確檢驗(yàn)，正態(tài)近似，連續(xù)性修正后的正態(tài)近似）

BM.test=function(x,y,alt) #alt:備擇假設(shè)形式

??{

??xy=c(x,y)

??md.xy=median(xy)

??t=sum(xy>md.xy)

??lx=length(x[x!=md.xy])

??ly=length(y[y!=md.xy])

??lxy=lx+ly

??A=sum(x>md.xy)#檢驗(yàn)統(tǒng)計(jì)量A

??z=(A-lx*t)/(lx+ly)/(lx*ly*t*(lx+ly-t)/(lx+ly)^3)^0.5#正態(tài)近似時(shí)的標(biāo)準(zhǔn)化統(tǒng)計(jì)量

??if(A>(min(lx,t)/2)){

? ? z1=(A+0.5-lx*t)/(lx+ly)/(lx*ly*t*(lx+ly-t)/(lx+ly)^3)^0.5#連續(xù)性修正后正態(tài)近似時(shí)的標(biāo)準(zhǔn)化統(tǒng)計(jì)量

??}

??else{z1=(A-0.5-lx*t)/(lx+ly)/(lx*ly*t*(lx+ly-t)/(lx+ly)^3)^0.5}

??if(alt=="greater"){

? ? pv1=1-phyper(A,lx,ly,t)#精確p值

? ? pv2=1-pnorm(z)#正態(tài)近似p值

? ? pv3=1-pnorm(z1)#連續(xù)性修正后正態(tài)近似p值

??}

??if(alt=="less"){

? ? pv1=phyper(A,lx,ly,t)

? ? pv2=pnorm(z)

? ? pv3=pnorm(z1)

??}

??if(alt=="two.sided"){

? ? pv1=2*min(1-phyper(A,lx,ly,t),phyper(A,lx,ly,t))

? ? pv2=2*min(1-pnorm(z),pnorm(z))

? ? pv3=2*min(1-pnorm(z1),pnorm(z1))

??}

??conting.table=matrix(c(A,lx-A,lx,t-A,ly-(t-A),ly,t,lxy-t,lxy),3,3)#計(jì)數(shù)表

??col.name=c("X","Y","X+Y")

??row.name=c(">MXY","<MXY","TOTAL")

??dimnames(conting.table)=list(row.name,col.name)

??list(contingency.table=conting.table,p.value=pv1,pvnorm=pv2,pvnr=pv3)

}