비지도학습 알고리즘 (1)

1.1.1 피어슨 상관 계수

• 두 변수 사이의 관련성을 파악하는 방법
• 공분산 / 표준편차
• 값은 -1에서 1사이

1.1.2 단순상관분석

autoparts=read.csv("data/autoparts.csv",header = TRUE)
autoparts1=autoparts[autoparts$prod_no=="90784-76001",c(2:11)]
autoparts2=autoparts1[autoparts1$c_thickness<1000,]

cor(autoparts2$separation,autoparts2$s_separation)

## [1] -0.9946107

1.1.3 다중상관분석

cor(autoparts2)

##                      fix_time     a_speed      b_speed    separation
## fix_time           1.00000000 -0.40965888 -0.053310788  0.6481035050
## a_speed           -0.40965888  1.00000000  0.094201813 -0.6297286266
## b_speed           -0.05331079  0.09420181  1.000000000 -0.0079536955
## separation         0.64810350 -0.62972863 -0.007953695  1.0000000000
## s_separation      -0.64955379  0.61663567  0.004768493 -0.9946106507
## rate_terms        -0.27573524  0.16379549  0.086763287 -0.4065543276
## mpa                0.01128835  0.42082145  0.065904868  0.0827314919
## load_time          0.02037007  0.39266555  0.022221837 -0.3181313349
## highpressure_time  0.01500145 -0.03609957 -0.013110064 -0.0007672313
## c_thickness       -0.06179651 -0.16476471  0.011748578 -0.1901120525
##                   s_separation   rate_terms          mpa   load_time
## fix_time          -0.649553792 -0.275735237  0.011288347  0.02037007
## a_speed            0.616635670  0.163795487  0.420821453  0.39266555
## b_speed            0.004768493  0.086763287  0.065904868  0.02222184
## separation        -0.994610651 -0.406554328  0.082731492 -0.31813133
## s_separation       1.000000000  0.417739099 -0.079472678  0.31399479
## rate_terms         0.417739099  1.000000000 -0.006729618  0.13530350
## mpa               -0.079472678 -0.006729618  1.000000000  0.22330961
## load_time          0.313994794  0.135303504  0.223309612  1.00000000
## highpressure_time -0.009468168 -0.015795293 -0.042117049 -0.02557634
## c_thickness        0.121676176  0.012913095 -0.579886953 -0.12169953
##                   highpressure_time c_thickness
## fix_time               0.0150014512 -0.06179651
## a_speed               -0.0360995659 -0.16476471
## b_speed               -0.0131100638  0.01174858
## separation            -0.0007672313 -0.19011205
## s_separation          -0.0094681675  0.12167618
## rate_terms            -0.0157952933  0.01291309
## mpa                   -0.0421170493 -0.57988695
## load_time             -0.0255763439 -0.12169953
## highpressure_time      1.0000000000  0.08522342
## c_thickness            0.0852234187  1.00000000

1.1.4 시각화 - symnum()

x=cor(autoparts2)
symnum(x)

##                   f a b sp s_ r m l h c
## fix_time          1                    
## a_speed           . 1                  
## b_speed               1                
## separation        , ,   1              
## s_separation      , ,   B  1           
## rate_terms              .  .  1        
## mpa                 .           1      
## load_time           .   .  .      1    
## highpressure_time                   1  
## c_thickness                     .     1
## attr(,"legend")
## [1] 0 ' ' 0.3 '.' 0.6 ',' 0.8 '+' 0.9 '*' 0.95 'B' 1

1.2.1