setwd("D:/data") #设定工作路径
d5.6=read.csv("C:\\Users\\86167\\Desktop\\ex5.6.csv",header=T) #读入数据
attach(d5.6) #用变量名绑定对应数据
library(MASS)
ld=lda(G~x1+x2+x3+x4, prior=c(17,21)/38,data=d5.6[1:38,])
Z=predict(ld)
newG = Z$class
cbind(G[1:38], newG, Z$post, Z$x) 
##        newG 1                      2                    LD1                 
## 1  "1" "1"  "0.951209074976659"    "0.0487909250233406" "-1.87498409300196" 
## 2  "1" "1"  "0.947804663736176"    "0.0521953362638236" "-1.83521998991981" 
## 3  "1" "1"  "0.791459854680252"    "0.208540145319748"  "-0.958924186613901"
## 4  "1" "1"  "0.733885655770335"    "0.266114344229665"  "-0.780172566716964"
## 5  "1" "1"  "0.810534931370835"    "0.189465068629165"  "-1.02595437016934" 
## 6  "1" "1"  "0.921548507869701"    "0.0784514921302992" "-1.59138750532567" 
## 7  "1" "1"  "0.951333049987091"    "0.0486669500129089" "-1.87648124680171" 
## 8  "1" "1"  "0.670900512806054"    "0.329099487193946"  "-0.61102357007802" 
## 9  "1" "1"  "0.575779945368292"    "0.424220054631708"  "-0.383308957820803"
## 10 "1" "1"  "0.929200838188875"    "0.0707991618111248" "-1.65346953044984" 
## 11 "1" "2"  "0.40148041566514"     "0.59851958433486"   "0.0112146283313096"
## 12 "1" "2"  "0.189404117594777"    "0.810595882405223"  "0.601558910446199" 
## 13 "1" "1"  "0.764309422520964"    "0.235690577479036"  "-0.87087255776738" 
## 14 "1" "1"  "0.744798644473102"    "0.255201355526898"  "-0.811875516049422"
## 15 "1" "1"  "0.80519426807303"     "0.19480573192697"   "-1.0066926355201"  
## 16 "1" "1"  "0.691069275091886"    "0.308930724908114"  "-0.663006705697663"
## 17 "1" "1"  "0.901563595421289"    "0.098436404578711"  "-1.45208154523264" 
## 18 "2" "2"  "0.061214489196187"    "0.938785510803813"  "1.31602499740894"  
## 19 "2" "2"  "0.498949674376309"    "0.501050325623691"  "-0.209956992703311"
## 20 "2" "2"  "0.0439167342941523"   "0.956083265705848"  "1.5121445941594"   
## 21 "2" "2"  "0.258568976339126"    "0.741431023660875"  "0.377382413012488" 
## 22 "2" "2"  "0.0162839458075177"   "0.983716054192482"  "2.08346830153382"  
## 23 "2" "2"  "0.0131376591463985"   "0.986862340853602"  "2.20544048587208"  
## 24 "2" "2"  "0.337248140112257"    "0.662751859887743"  "0.165873404289155" 
## 25 "2" "1"  "0.569021773467342"    "0.430978226532658"  "-0.367852045832071"
## 26 "2" "2"  "0.230513108007367"    "0.769486891992633"  "0.462468194163585" 
## 27 "2" "2"  "0.47860817968787"     "0.52139182031213"   "-0.164380072925443"
## 28 "2" "2"  "0.377165886679261"    "0.622834113320739"  "0.0684778827330926"
## 29 "2" "2"  "0.114079343418433"    "0.885920656581567"  "0.935106376696436" 
## 30 "2" "1"  "0.802686309790678"    "0.197313690209322"  "-0.997785537025995"
## 31 "2" "2"  "0.261719150965792"    "0.738280849034208"  "0.368220188872751" 
## 32 "2" "1"  "0.61484480565648"     "0.38515519434352"   "-0.474134663319322"
## 33 "2" "2"  "0.220544080486415"    "0.779455919513585"  "0.494422191413581" 
## 34 "2" "2"  "0.00394884581450975"  "0.99605115418549"   "2.88352663094246"  
## 35 "2" "2"  "0.32906843222442"     "0.67093156777558"   "0.186484640845839" 
## 36 "2" "2"  "0.042650876098849"    "0.957349123901151"  "1.52925772169081"  
## 37 "2" "2"  "0.190740485451104"    "0.809259514548897"  "0.596699476623414" 
## 38 "2" "2"  "0.000754558268053544" "0.999245441731947"  "3.811793249936"
tab=table(G[1:38], newG)
tab
##    newG
##      1  2
##   1 15  2
##   2  3 18
sum(diag(prop.table(tab))) #计算回判正确率
## [1] 0.8684211

##回判正确率是约为87%

newdata= d5.6[39:46, 2:5] 
predict(ld, newdata= newdata)
## $class
## [1] 1 1 1 1 2 2 2 2
## Levels: 1 2
## 
## $posterior
##             1         2
## 39 0.74485549 0.2551445
## 40 0.78380127 0.2161987
## 41 0.65829504 0.3417050
## 42 0.80932892 0.1906711
## 43 0.36582186 0.6341781
## 44 0.24701801 0.7529820
## 45 0.28037669 0.7196233
## 46 0.06243681 0.9375632
## 
## $x
##           LD1
## 39 -0.8120429
## 40 -0.9332914
## 41 -0.5793647
## 42 -1.0215689
## 43  0.0956770
## 44  0.4116193
## 45  0.3153435
## 46  1.3042280

##其中前4个样品被预测为类别1(对应破产企业),后4个样品被预测为类别2(对应正常运行企业)。