Exercise 6.2 The data set criminal in the package logmult gives the 4 × 5 table below of the number of men aged 15-19 charged with a criminal case for whom charges were dropped in Denmark from 1955-1958.
data("criminal", package="logmult")
criminal
## Age
## Year 15 16 17 18 19
## 1955 141 285 320 441 427
## 1956 144 292 342 441 396
## 1957 196 380 424 462 427
## 1958 212 424 399 442 430
(a)What percentages of the Pearson ??2 for association are explained by the various dimensions?
library(ca)
## Warning: package 'ca' was built under R version 3.4.4
criminal.ca <- ca(criminal)
summary(criminal.ca)
##
## Principal inertias (eigenvalues):
##
## dim value % cum% scree plot
## 1 0.004939 90.3 90.3 ***********************
## 2 0.000491 9.0 99.3 **
## 3 3.8e-050 0.7 100.0
## -------- -----
## Total: 0.005468 100.0
##
##
## Rows:
## name mass qlt inr k=1 cor ctr k=2 cor ctr
## 1 | 1955 | 230 996 347 | 88 939 361 | -22 58 223 |
## 2 | 1956 | 230 978 157 | 58 908 157 | 16 71 124 |
## 3 | 1957 | 269 984 111 | -39 669 82 | 27 315 391 |
## 4 | 1958 | 271 999 385 | -85 938 399 | -22 61 262 |
##
## Columns:
## name mass qlt inr k=1 cor ctr k=2 cor ctr
## 1 | 15 | 99 998 185 | -101 992 203 | -7 5 11 |
## 2 | 16 | 197 996 312 | -91 959 331 | -18 37 128 |
## 3 | 17 | 211 991 75 | -23 281 23 | 37 710 594 |
## 4 | 18 | 254 989 235 | 70 980 255 | 7 9 24 |
## 5 | 19 | 239 990 194 | 62 877 188 | -22 112 243 |
This indicated that 99.3% of the model is accounted for first two variables
plot(criminal.ca)
From this graph we can see that younger demography is associated with later years and vice versa.
Exercise 6.11 The data set Vietnam in vcdExtra gives a 2 × 5 × 4 contingency table in frequency form reflecting a survey of student opinion on the Vietnam War at the University of North Carolina in May 1967. The table variables are sex, year in school, and response, which has categories: (A) Defeat North Vietnam by widespread bombing and land invasion; (B) Maintain the present policy; (C) De-escalate military activity, stop bombing and begin negotiations; (D) Withdraw military forces immediately.
library(vcd)
## Warning: package 'vcd' was built under R version 3.4.4
## Loading required package: grid
data("Vietnam",package="vcdExtra")
str(Vietnam)
## 'data.frame': 40 obs. of 4 variables:
## $ sex : Factor w/ 2 levels "Female","Male": 1 1 1 1 1 1 1 1 1 1 ...
## $ year : int 1 1 1 1 2 2 2 2 3 3 ...
## $ response: Factor w/ 4 levels "A","B","C","D": 1 2 3 4 1 2 3 4 1 2 ...
## $ Freq : int 13 19 40 5 5 9 33 3 22 29 ...
Vietnam
## sex year response Freq
## 1 Female 1 A 13
## 2 Female 1 B 19
## 3 Female 1 C 40
## 4 Female 1 D 5
## 5 Female 2 A 5
## 6 Female 2 B 9
## 7 Female 2 C 33
## 8 Female 2 D 3
## 9 Female 3 A 22
## 10 Female 3 B 29
## 11 Female 3 C 110
## 12 Female 3 D 6
## 13 Female 4 A 12
## 14 Female 4 B 21
## 15 Female 4 C 58
## 16 Female 4 D 10
## 17 Female 5 A 19
## 18 Female 5 B 27
## 19 Female 5 C 128
## 20 Female 5 D 13
## 21 Male 1 A 175
## 22 Male 1 B 116
## 23 Male 1 C 131
## 24 Male 1 D 17
## 25 Male 2 A 160
## 26 Male 2 B 126
## 27 Male 2 C 135
## 28 Male 2 D 21
## 29 Male 3 A 132
## 30 Male 3 B 120
## 31 Male 3 C 154
## 32 Male 3 D 29
## 33 Male 4 A 145
## 34 Male 4 B 95
## 35 Male 4 C 185
## 36 Male 4 D 44
## 37 Male 5 A 118
## 38 Male 5 B 176
## 39 Male 5 C 345
## 40 Male 5 D 141
Vietnam <- within(Vietnam, {year_sex <- paste(year, toupper(substr(sex,1,1)))})
Vietnam
## sex year response Freq year_sex
## 1 Female 1 A 13 1 F
## 2 Female 1 B 19 1 F
## 3 Female 1 C 40 1 F
## 4 Female 1 D 5 1 F
## 5 Female 2 A 5 2 F
## 6 Female 2 B 9 2 F
## 7 Female 2 C 33 2 F
## 8 Female 2 D 3 2 F
## 9 Female 3 A 22 3 F
## 10 Female 3 B 29 3 F
## 11 Female 3 C 110 3 F
## 12 Female 3 D 6 3 F
## 13 Female 4 A 12 4 F
## 14 Female 4 B 21 4 F
## 15 Female 4 C 58 4 F
## 16 Female 4 D 10 4 F
## 17 Female 5 A 19 5 F
## 18 Female 5 B 27 5 F
## 19 Female 5 C 128 5 F
## 20 Female 5 D 13 5 F
## 21 Male 1 A 175 1 M
## 22 Male 1 B 116 1 M
## 23 Male 1 C 131 1 M
## 24 Male 1 D 17 1 M
## 25 Male 2 A 160 2 M
## 26 Male 2 B 126 2 M
## 27 Male 2 C 135 2 M
## 28 Male 2 D 21 2 M
## 29 Male 3 A 132 3 M
## 30 Male 3 B 120 3 M
## 31 Male 3 C 154 3 M
## 32 Male 3 D 29 3 M
## 33 Male 4 A 145 4 M
## 34 Male 4 B 95 4 M
## 35 Male 4 C 185 4 M
## 36 Male 4 D 44 4 M
## 37 Male 5 A 118 5 M
## 38 Male 5 B 176 5 M
## 39 Male 5 C 345 5 M
## 40 Male 5 D 141 5 M
Vietnam.tab <- xtabs(Freq ~ year_sex + response, data=Vietnam)
Vietnam.tab
## response
## year_sex A B C D
## 1 F 13 19 40 5
## 1 M 175 116 131 17
## 2 F 5 9 33 3
## 2 M 160 126 135 21
## 3 F 22 29 110 6
## 3 M 132 120 154 29
## 4 F 12 21 58 10
## 4 M 145 95 185 44
## 5 F 19 27 128 13
## 5 M 118 176 345 141
Vietnam.ca <- ca(Vietnam.tab)
summary(Vietnam.ca)
##
## Principal inertias (eigenvalues):
##
## dim value % cum% scree plot
## 1 0.085680 73.6 73.6 ******************
## 2 0.027881 23.9 97.5 ******
## 3 0.002854 2.5 100.0 *
## -------- -----
## Total: 0.116415 100.0
##
##
## Rows:
## name mass qlt inr k=1 cor ctr k=2 cor ctr
## 1 | 1F | 24 818 13 | -167 452 8 | -150 367 20 |
## 2 | 1M | 139 997 181 | 386 986 242 | -41 11 8 |
## 3 | 2F | 16 995 35 | -407 647 31 | -299 349 51 |
## 4 | 2M | 140 984 131 | 326 982 175 | -15 2 1 |
## 5 | 3F | 53 999 112 | -334 453 69 | -367 547 256 |
## 6 | 3M | 138 904 40 | 175 904 49 | -4 0 0 |
## 7 | 4F | 32 982 37 | -344 887 44 | -113 95 15 |
## 8 | 4M | 149 383 23 | 81 372 11 | 14 11 1 |
## 9 | 5F | 59 994 153 | -453 686 143 | -304 309 197 |
## 10 | 5M | 248 1000 276 | -281 608 228 | 225 391 451 |
##
## Columns:
## name mass qlt inr k=1 cor ctr k=2 cor ctr
## 1 | A | 255 985 381 | 414 985 509 | -1 0 0 |
## 2 | B | 235 720 60 | 135 608 50 | 58 112 28 |
## 3 | C | 419 999 283 | -247 773 298 | -133 226 267 |
## 4 | D | 92 995 276 | -366 383 143 | 463 612 705 |
plot(Vietnam.ca)
From the plot we can interpret the preferences of males and female officers during the year. For example males in year 5 prefer D, likewise women prefer C.
Vietnam.mca <- mjca(Vietnam.tab)
summary(Vietnam.mca)
##
## Principal inertias (eigenvalues):
##
## dim value % cum% scree plot
## 1 0.085680 73.6 73.6 ******************
## 2 0.027881 23.9 97.5 ******
## 3 0.002854 2.5 100.0 *
## 4 00000000 0.0 100.0
## 5 00000000 0.0 100.0
## 6 00000000 0.0 100.0
## 7 00000000 0.0 100.0
## -------- -----
## Total: 0.116415
##
##
## Columns:
## name mass qlt inr k=1 cor ctr k=2 cor ctr
## 1 | year_sex:1 F | 12 818 80 | 167 452 4 | -150 367 10 |
## 2 | year_sex:1 M | 70 997 72 | -386 986 121 | -41 11 4 |
## 3 | year_sex:2 F | 8 995 81 | 407 647 15 | -299 349 25 |
## 4 | year_sex:2 M | 70 984 72 | -326 982 87 | -15 2 1 |
## 5 | year_sex:3 F | 27 999 78 | 334 453 34 | -367 547 128 |
## 6 | year_sex:3 M | 69 904 71 | -175 904 25 | -4 0 0 |
## 7 | year_sex:4 F | 16 982 79 | 344 887 22 | -113 95 7 |
## 8 | year_sex:4 M | 75 383 70 | -81 372 6 | 14 11 1 |
## 9 | year_sex:5 F | 30 994 78 | 453 686 71 | -304 309 99 |
## 10 | year_sex:5 M | 124 1000 64 | 281 608 114 | 225 391 225 |
## 11 | response:A | 127 985 65 | -414 985 255 | -1 0 0 |
## 12 | response:B | 117 720 63 | -135 608 25 | 58 112 14 |
## 13 | response:C | 210 999 50 | 247 773 149 | -133 226 134 |
## 14 | response:D | 46 995 77 | 366 383 72 | 463 612 352 |
plot(Vietnam.mca)
The outcomes are similar to the previous results and highlighted that responses preferences over years change for males and stay constant for female.