Method #1. Tree-based classification

Step 1: Collecting the data

credit <- read.csv("credit.csv")
str(credit)
## 'data.frame':    1000 obs. of  17 variables:
##  $ checking_balance    : Factor w/ 4 levels "< 0 DM","> 200 DM",..: 1 3 4 1 1 4 4 3 4 3 ...
##  $ months_loan_duration: int  6 48 12 42 24 36 24 36 12 30 ...
##  $ credit_history      : Factor w/ 5 levels "critical","good",..: 1 2 1 2 4 2 2 2 2 1 ...
##  $ purpose             : Factor w/ 6 levels "business","car",..: 5 5 4 5 2 4 5 2 5 2 ...
##  $ amount              : int  1169 5951 2096 7882 4870 9055 2835 6948 3059 5234 ...
##  $ savings_balance     : Factor w/ 5 levels "< 100 DM","> 1000 DM",..: 5 1 1 1 1 5 4 1 2 1 ...
##  $ employment_duration : Factor w/ 5 levels "< 1 year","> 7 years",..: 2 3 4 4 3 3 2 3 4 5 ...
##  $ percent_of_income   : int  4 2 2 2 3 2 3 2 2 4 ...
##  $ years_at_residence  : int  4 2 3 4 4 4 4 2 4 2 ...
##  $ age                 : int  67 22 49 45 53 35 53 35 61 28 ...
##  $ other_credit        : Factor w/ 3 levels "bank","none",..: 2 2 2 2 2 2 2 2 2 2 ...
##  $ housing             : Factor w/ 3 levels "other","own",..: 2 2 2 1 1 1 2 3 2 2 ...
##  $ existing_loans_count: int  2 1 1 1 2 1 1 1 1 2 ...
##  $ job                 : Factor w/ 4 levels "management","skilled",..: 2 2 4 2 2 4 2 1 4 1 ...
##  $ dependents          : int  1 1 2 2 2 2 1 1 1 1 ...
##  $ phone               : Factor w/ 2 levels "no","yes": 2 1 1 1 1 2 1 2 1 1 ...
##  $ default             : Factor w/ 2 levels "no","yes": 1 2 1 1 2 1 1 1 1 2 ...

Step 2: Exploring the data

summary(credit$amount)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##     250    1366    2320    3271    3972   18424
table(credit$default)
## 
##  no yes 
## 700 300
set.seed(12345)
credit_rand <- credit[order(runif(1000)), ]
summary(credit$amount)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##     250    1366    2320    3271    3972   18424
summary(credit_rand$amount)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##     250    1366    2320    3271    3972   18424
credit_train <- credit_rand[1:900, ]
credit_test <- credit_rand[901:1000, ]
prop.table(table(credit_train$default))
## 
##        no       yes 
## 0.7022222 0.2977778
prop.table(table(credit_test$default))
## 
##   no  yes 
## 0.68 0.32

Step 3: Training a model on the data

library(C50)
credit_model <- C5.0(x = credit_train[-17], y = credit_train$default)
summary(credit_model)
## 
## Call:
## C5.0.default(x = credit_train[-17], y = credit_train$default)
## 
## 
## C5.0 [Release 2.07 GPL Edition]      Sun Jul  1 01:34:20 2018
## -------------------------------
## 
## Class specified by attribute `outcome'
## 
## Read 900 cases (17 attributes) from undefined.data
## 
## Decision tree:
## 
## checking_balance = unknown: no (358/44)
## checking_balance in {< 0 DM,> 200 DM,1 - 200 DM}:
## :...credit_history in {perfect,very good}:
##     :...dependents > 1: yes (10/1)
##     :   dependents <= 1:
##     :   :...savings_balance = < 100 DM: yes (39/11)
##     :       savings_balance in {> 1000 DM,500 - 1000 DM,unknown}: no (8/1)
##     :       savings_balance = 100 - 500 DM:
##     :       :...checking_balance = < 0 DM: no (1)
##     :           checking_balance in {> 200 DM,1 - 200 DM}: yes (5/1)
##     credit_history in {critical,good,poor}:
##     :...months_loan_duration <= 11: no (87/14)
##         months_loan_duration > 11:
##         :...savings_balance = > 1000 DM: no (13)
##             savings_balance in {< 100 DM,100 - 500 DM,500 - 1000 DM,unknown}:
##             :...checking_balance = > 200 DM:
##                 :...dependents > 1: yes (3)
##                 :   dependents <= 1:
##                 :   :...credit_history in {good,poor}: no (23/3)
##                 :       credit_history = critical:
##                 :       :...amount <= 2337: yes (3)
##                 :           amount > 2337: no (6)
##                 checking_balance = 1 - 200 DM:
##                 :...savings_balance = unknown: no (34/6)
##                 :   savings_balance in {< 100 DM,100 - 500 DM,500 - 1000 DM}:
##                 :   :...months_loan_duration > 45: yes (11/1)
##                 :       months_loan_duration <= 45:
##                 :       :...other_credit = store:
##                 :           :...age <= 35: yes (4)
##                 :           :   age > 35: no (2)
##                 :           other_credit = bank:
##                 :           :...years_at_residence <= 1: no (3)
##                 :           :   years_at_residence > 1:
##                 :           :   :...existing_loans_count <= 1: yes (5)
##                 :           :       existing_loans_count > 1:
##                 :           :       :...percent_of_income <= 2: no (4/1)
##                 :           :           percent_of_income > 2: yes (3)
##                 :           other_credit = none:
##                 :           :...job = unemployed: no (1)
##                 :               job = management:
##                 :               :...amount <= 7511: no (10/3)
##                 :               :   amount > 7511: yes (7)
##                 :               job = unskilled: [S1]
##                 :               job = skilled:
##                 :               :...dependents <= 1: no (55/15)
##                 :                   dependents > 1:
##                 :                   :...age <= 34: no (3)
##                 :                       age > 34: yes (4)
##                 checking_balance = < 0 DM:
##                 :...job = management: no (26/6)
##                     job = unemployed: yes (4/1)
##                     job = unskilled:
##                     :...employment_duration in {4 - 7 years,
##                     :   :                       unemployed}: no (4)
##                     :   employment_duration = < 1 year:
##                     :   :...other_credit = bank: no (1)
##                     :   :   other_credit in {none,store}: yes (11/2)
##                     :   employment_duration = > 7 years:
##                     :   :...other_credit in {bank,none}: no (5/1)
##                     :   :   other_credit = store: yes (2)
##                     :   employment_duration = 1 - 4 years:
##                     :   :...age <= 39: no (14/3)
##                     :       age > 39:
##                     :       :...credit_history in {critical,good}: yes (3)
##                     :           credit_history = poor: no (1)
##                     job = skilled:
##                     :...credit_history = poor:
##                         :...savings_balance in {< 100 DM,100 - 500 DM,
##                         :   :                   500 - 1000 DM}: yes (8)
##                         :   savings_balance = unknown: no (1)
##                         credit_history = critical:
##                         :...other_credit = store: no (0)
##                         :   other_credit = bank: yes (4)
##                         :   other_credit = none:
##                         :   :...savings_balance in {100 - 500 DM,
##                         :       :                   unknown}: no (1)
##                         :       savings_balance = 500 - 1000 DM: yes (1)
##                         :       savings_balance = < 100 DM:
##                         :       :...months_loan_duration <= 13:
##                         :           :...percent_of_income <= 3: yes (3)
##                         :           :   percent_of_income > 3: no (3/1)
##                         :           months_loan_duration > 13:
##                         :           :...amount <= 5293: no (10/1)
##                         :               amount > 5293: yes (2)
##                         credit_history = good:
##                         :...existing_loans_count > 1: yes (5)
##                             existing_loans_count <= 1:
##                             :...other_credit = store: no (2)
##                                 other_credit = bank:
##                                 :...percent_of_income <= 2: yes (2)
##                                 :   percent_of_income > 2: no (6/1)
##                                 other_credit = none: [S2]
## 
## SubTree [S1]
## 
## employment_duration in {< 1 year,1 - 4 years}: yes (11/3)
## employment_duration in {> 7 years,4 - 7 years,unemployed}: no (8)
## 
## SubTree [S2]
## 
## savings_balance = 100 - 500 DM: yes (3)
## savings_balance = 500 - 1000 DM: no (1)
## savings_balance = unknown:
## :...phone = no: yes (9/1)
## :   phone = yes: no (3/1)
## savings_balance = < 100 DM:
## :...percent_of_income <= 1: no (4)
##     percent_of_income > 1:
##     :...phone = yes: yes (10/1)
##         phone = no:
##         :...purpose in {business,car0,education,renovations}: yes (3)
##             purpose = car:
##             :...percent_of_income <= 3: no (2)
##             :   percent_of_income > 3: yes (6/1)
##             purpose = furniture/appliances:
##             :...years_at_residence <= 1: no (4)
##                 years_at_residence > 1:
##                 :...housing = other: no (1)
##                     housing = rent: yes (2)
##                     housing = own:
##                     :...amount <= 1778: no (3)
##                         amount > 1778:
##                         :...years_at_residence <= 3: yes (6)
##                             years_at_residence > 3: no (3/1)
## 
## 
## Evaluation on training data (900 cases):
## 
##      Decision Tree   
##    ----------------  
##    Size      Errors  
## 
##      66  125(13.9%)   <<
## 
## 
##     (a)   (b)    <-classified as
##    ----  ----
##     609    23    (a): class no
##     102   166    (b): class yes
## 
## 
##  Attribute usage:
## 
##  100.00% checking_balance
##   60.22% credit_history
##   53.22% months_loan_duration
##   49.44% savings_balance
##   30.89% job
##   25.89% other_credit
##   17.78% dependents
##    9.67% existing_loans_count
##    7.22% percent_of_income
##    6.67% employment_duration
##    5.78% phone
##    5.56% amount
##    3.78% years_at_residence
##    3.44% age
##    3.33% purpose
##    1.67% housing
## 
## 
## Time: 0.0 secs

Step 4: Evaluating Model Performance

cred_pred <- predict(credit_model, credit_test)
library(gmodels)
CrossTable(credit_test$default, cred_pred, prop.chisq = FALSE, prop.c = FALSE, prop.r = FALSE, dnn = c('actua l default', 'predicted default'))
## 
##  
##    Cell Contents
## |-------------------------|
## |                       N |
## |         N / Table Total |
## |-------------------------|
## 
##  
## Total Observations in Table:  100 
## 
##  
##                 | predicted default 
## actua l default |        no |       yes | Row Total | 
## ----------------|-----------|-----------|-----------|
##              no |        57 |        11 |        68 | 
##                 |     0.570 |     0.110 |           | 
## ----------------|-----------|-----------|-----------|
##             yes |        16 |        16 |        32 | 
##                 |     0.160 |     0.160 |           | 
## ----------------|-----------|-----------|-----------|
##    Column Total |        73 |        27 |       100 | 
## ----------------|-----------|-----------|-----------|
## 
## 

Method #2. Support vector machines

Step 1: Collecting the data

letters <- read.csv("letterdata.csv")
str(letters)
## 'data.frame':    20000 obs. of  17 variables:
##  $ letter: Factor w/ 26 levels "A","B","C","D",..: 20 9 4 14 7 19 2 1 10 13 ...
##  $ xbox  : int  2 5 4 7 2 4 4 1 2 11 ...
##  $ ybox  : int  8 12 11 11 1 11 2 1 2 15 ...
##  $ width : int  3 3 6 6 3 5 5 3 4 13 ...
##  $ height: int  5 7 8 6 1 8 4 2 4 9 ...
##  $ onpix : int  1 2 6 3 1 3 4 1 2 7 ...
##  $ xbar  : int  8 10 10 5 8 8 8 8 10 13 ...
##  $ ybar  : int  13 5 6 9 6 8 7 2 6 2 ...
##  $ x2bar : int  0 5 2 4 6 6 6 2 2 6 ...
##  $ y2bar : int  6 4 6 6 6 9 6 2 6 2 ...
##  $ xybar : int  6 13 10 4 6 5 7 8 12 12 ...
##  $ x2ybar: int  10 3 3 4 5 6 6 2 4 1 ...
##  $ xy2bar: int  8 9 7 10 9 6 6 8 8 9 ...
##  $ xedge : int  0 2 3 6 1 0 2 1 1 8 ...
##  $ xedgey: int  8 8 7 10 7 8 8 6 6 1 ...
##  $ yedge : int  0 4 3 2 5 9 7 2 1 1 ...
##  $ yedgex: int  8 10 9 8 10 7 10 7 7 8 ...

Step 2: Preparing the Data

letters_train <- letters[1:18000, ]
letters_test <- letters[18001:20000, ]

Step 3: Training a Model on the Data

library(kernlab)
letter_classifier <- ksvm(letter ~ ., data = letters_train, kernel = "vanilladot")
##  Setting default kernel parameters
letter_classifier
## Support Vector Machine object of class "ksvm" 
## 
## SV type: C-svc  (classification) 
##  parameter : cost C = 1 
## 
## Linear (vanilla) kernel function. 
## 
## Number of Support Vectors : 7886 
## 
## Objective Function Value : -15.3458 -21.3403 -25.7672 -6.8685 -8.8812 -35.9555 -59.5883 -18.1975 -65.6075 -41.5654 -18.8559 -39.3558 -36.9961 -60.3052 -15.1694 -42.144 -35.0941 -19.4069 -15.8234 -38.6718 -33.3013 -8.5298 -12.4387 -38.2194 -14.3682 -9.5508 -165.7154 -53.2778 -79.2163 -134.5053 -184.4809 -58.9285 -46.3252 -81.004 -28.1341 -29.6955 -27.5983 -38.1764 -47.2889 -137.0497 -208.1396 -239.2616 -23.8945 -10.9655 -64.228 -12.2139 -55.7818 -10.8001 -21.2407 -11.1795 -121.5639 -33.2229 -267.3926 -81.0708 -9.4937 -4.6577 -161.5171 -86.7114 -20.9146 -16.8272 -86.6582 -16.7205 -30.3036 -20.0054 -26.2331 -29.9289 -56.1072 -11.6335 -5.2564 -14.8153 -4.983 -4.8171 -8.5044 -43.2267 -55.9 -214.755 -47.0748 -49.6539 -50.2278 -18.3767 -19.1813 -97.6132 -113.6502 -42.4112 -32.5859 -127.4807 -33.7418 -30.7568 -40.0953 -18.6792 -5.4826 -49.3916 -10.6142 -20.0286 -63.8287 -183.8297 -57.0671 -43.3721 -35.2783 -85.4451 -145.9585 -11.8002 -6.1194 -12.5323 -33.5245 -155.2248 -57.2602 -194.0785 -111.0155 -10.8207 -16.7926 -3.7766 -77.3561 -7.9004 -106.5759 -52.523 -107.0402 -78.0148 -74.4773 -24.8166 -13.2372 -7.8706 -27.2788 -13.2342 -280.2869 -32.7288 -25.9531 -149.5447 -153.8495 -10.0146 -40.8917 -6.7333 -65.2053 -72.818 -35.1252 -246.7046 -38.0738 -16.9126 -158.18 -184.0021 -50.8427 -28.7686 -164.5969 -97.8359 -386.1426 -160.3188 -181.8759 -38.3648 -37.2272 -60.116 -28.2074 -53.7383 -7.8729 -12.3159 -37.8942 -72.6434 -211.8342 -58.5023 -105.1605 -176.7259 -685.8994 -142.8147 -159.635 -366.9437 -37.6409 -73.1357 -175.1906 -131.2833 -41.1464 -77.8404 -57.8131 -8.6365 -251.3728 -14.0836 -36.5144 -2.2292 -6.1598 -16.8011 -26.5165 -67.19 -21.3366 -221.4815 -22.9219 -4.2616 -4.7901 -0.8263 -134.7538 -8.8843 -83.1109 -23.1019 -14.4251 -5.7337 -17.5244 -29.7925 -23.9243 -88.9084 -28.6719 -106.0564 -16.4981 -10.6486 -7.9315 -1.5742 -91.1706 -7.3819 -118.2628 -117.5543 -48.5606 -26.6093 -71.2968 -30.4913 -63.5712 -279.2921 -46.3025 -50.4912 -37.9431 -21.5243 -11.6202 -134.9023 -7.516 -5.8131 -10.1595 -13.6329 -27.0293 -25.7282 -151.8511 -39.0524 -105.4861 -34.2434 -15.7051 -10.2304 -3.6687 -98.2094 -7.4666 -15.2668 -75.1283 -116.5382 -16.6429 -14.9215 -55.1062 -3.0636 -8.4262 -93.6829 -38.1162 -123.1859 -4.9078 -9.1612 -1.3077 -102.9021 -23.1138 -8.5262 -57.2623 -3.4297 -20.9579 -78.2019 -50.3741 -62.3531 -6.4908 -21.9308 -2.3736 -84.3835 -126.3997 -114.8723 -26.4109 -21.5589 -61.6405 -34.9162 -66.3243 -25.1148 -6.7203 -4.6695 -65.3518 -39.7924 -67.3505 -36.2154 -10.9031 -62.2195 -14.9491 -24.3238 -65.0847 -4.9657 -64.2797 -278.2873 -14.6902 -13.9198 -18.2059 -9.8972 -78.2645 -17.454 -49.5929 -55.7786 -28.7673 -15.9476 -47.531 -17.4379 -71.0516 -5.6899 -6.2519 -97.5508 -3.8196 -7.0502 -1.1238 -147.6952 -28.2018 -414.2586 -32.3275 -35.1191 -4.9605 -90.2307 -151.3409 -90.0329 -27.9491 -42.4688 -12.5118 -26.4828 -2.0045 -62.195 -9.1662 -178.4616 -1.9406 -1.9871 -11.3982 -0.5214 -29.6136 -35.0449 -6.7569 
## Training error : 0.1335

Step 4: Evaluating Model Performance

letter_predictions <- predict(letter_classifier, letters_test)
table(letter_predictions, letters_test$letter)
##                   
## letter_predictions  A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R
##                  A 73  0  0  0  0  0  0  0  0  1  0  0  0  0  3  0  4  0
##                  B  0 61  0  3  2  0  1  1  0  0  1  1  0  0  0  2  0  1
##                  C  0  0 64  0  2  0  4  2  1  0  1  2  0  0  1  0  0  0
##                  D  2  1  0 67  0  0  1  3  3  2  1  2  0  3  4  2  1  2
##                  E  0  0  1  0 64  1  1  0  0  0  2  2  0  0  0  0  2  0
##                  F  0  0  0  0  0 70  1  1  4  0  0  0  0  0  0  5  1  0
##                  G  1  1  2  1  3  2 68  1  0  0  0  1  0  0  0  0  4  1
##                  H  0  0  0  1  0  1  0 46  0  2  3  1  1  1  9  0  0  5
##                  I  0  0  0  0  0  0  0  0 65  3  0  0  0  0  0  0  0  0
##                  J  0  1  0  0  0  1  0  0  3 61  0  0  0  0  1  0  0  0
##                  K  0  1  4  0  0  0  0  5  0  0 56  0  0  2  0  0  0  4
##                  L  0  0  0  0  1  0  0  1  0  0  0 63  0  0  0  0  0  0
##                  M  0  0  1  0  0  0  1  0  0  0  0  0 70  2  0  0  0  0
##                  N  0  0  0  0  0  0  0  0  0  0  0  0  0 77  0  0  0  1
##                  O  0  0  1  1  0  0  0  1  0  1  0  0  0  0 49  1  2  0
##                  P  0  0  0  0  0  3  0  0  0  0  0  0  0  0  2 69  0  0
##                  Q  0  0  0  0  0  0  3  1  0  0  0  2  0  0  2  1 52  0
##                  R  0  4  0  0  1  0  0  3  0  0  3  0  0  0  1  0  0 64
##                  S  0  1  0  0  1  1  1  0  1  1  0  0  0  0  0  0  6  0
##                  T  0  0  0  0  1  1  0  0  0  0  1  0  0  0  0  0  0  0
##                  U  0  0  2  1  0  0  0  1  0  0  0  0  0  0  0  0  0  0
##                  V  0  0  0  0  0  0  0  0  0  0  0  0  1  0  1  0  0  0
##                  W  0  0  0  0  0  0  0  0  0  0  0  0  1  0  0  0  0  0
##                  X  0  1  0  0  1  0  0  1  0  0  1  4  0  0  0  0  0  1
##                  Y  2  0  0  0  0  0  0  0  0  0  0  0  0  0  0  4  0  0
##                  Z  1  0  0  0  2  0  0  0  0  2  0  0  0  0  0  0  0  0
##                   
## letter_predictions  S  T  U  V  W  X  Y  Z
##                  A  0  1  2  0  1  0  0  0
##                  B  3  0  0  0  0  0  0  0
##                  C  0  0  0  0  0  0  0  0
##                  D  0  0  0  0  0  0  1  0
##                  E  6  0  0  0  0  1  0  0
##                  F  2  0  0  1  0  0  2  0
##                  G  3  2  0  0  0  0  0  0
##                  H  0  3  0  2  0  0  1  0
##                  I  2  0  0  0  0  2  1  0
##                  J  1  0  0  0  0  1  0  4
##                  K  0  1  2  0  0  4  0  0
##                  L  0  0  0  0  0  0  0  0
##                  M  0  0  1  0  6  0  0  0
##                  N  0  0  1  0  2  0  0  0
##                  O  0  0  1  0  0  0  0  0
##                  P  0  0  0  0  0  0  1  0
##                  Q  1  0  0  0  0  0  0  0
##                  R  0  1  0  1  0  0  0  0
##                  S 47  1  0  0  0  1  0  6
##                  T  1 83  1  0  0  0  2  2
##                  U  0  0 83  0  0  0  0  0
##                  V  0  0  0 64  1  0  1  0
##                  W  0  0  0  3 59  0  0  0
##                  X  0  0  0  0  0 76  1  0
##                  Y  0  1  0  0  0  1 58  0
##                  Z  5  1  0  0  0  0  0 70
agreement <- letter_predictions == letters_test$letter
table(agreement)
## agreement
## FALSE  TRUE 
##   321  1679

Method #3. Adding regression to trees

Step 1: Collecting the data

wine <- read.csv("whitewines.csv")
str(wine)
## 'data.frame':    4898 obs. of  12 variables:
##  $ fixed.acidity       : num  6.7 5.7 5.9 5.3 6.4 7 7.9 6.6 7 6.5 ...
##  $ volatile.acidity    : num  0.62 0.22 0.19 0.47 0.29 0.14 0.12 0.38 0.16 0.37 ...
##  $ citric.acid         : num  0.24 0.2 0.26 0.1 0.21 0.41 0.49 0.28 0.3 0.33 ...
##  $ residual.sugar      : num  1.1 16 7.4 1.3 9.65 0.9 5.2 2.8 2.6 3.9 ...
##  $ chlorides           : num  0.039 0.044 0.034 0.036 0.041 0.037 0.049 0.043 0.043 0.027 ...
##  $ free.sulfur.dioxide : num  6 41 33 11 36 22 33 17 34 40 ...
##  $ total.sulfur.dioxide: num  62 113 123 74 119 95 152 67 90 130 ...
##  $ density             : num  0.993 0.999 0.995 0.991 0.993 ...
##  $ pH                  : num  3.41 3.22 3.49 3.48 2.99 3.25 3.18 3.21 2.88 3.28 ...
##  $ sulphates           : num  0.32 0.46 0.42 0.54 0.34 0.43 0.47 0.47 0.47 0.39 ...
##  $ alcohol             : num  10.4 8.9 10.1 11.2 10.9 ...
##  $ quality             : int  5 6 6 4 6 6 6 6 6 7 ...
hist(wine$quality)

Step 2: Exploring and Preparing the Data

wine_train <- wine[1:3750, ]
wine_test <- wine[3751:4898, ]

Step 3: Training a Model on the Data

library(rpart)
library(rpart.plot)
m.rpart <- rpart(quality ~ ., data=wine_train)
m.rpart
## n= 3750 
## 
## node), split, n, deviance, yval
##       * denotes terminal node
## 
##  1) root 3750 2945.53200 5.870933  
##    2) alcohol< 10.85 2372 1418.86100 5.604975  
##      4) volatile.acidity>=0.2275 1611  821.30730 5.432030  
##        8) volatile.acidity>=0.3025 688  278.97670 5.255814 *
##        9) volatile.acidity< 0.3025 923  505.04230 5.563380 *
##      5) volatile.acidity< 0.2275 761  447.36400 5.971091 *
##    3) alcohol>=10.85 1378 1070.08200 6.328737  
##      6) free.sulfur.dioxide< 10.5 84   95.55952 5.369048 *
##      7) free.sulfur.dioxide>=10.5 1294  892.13600 6.391036  
##       14) alcohol< 11.76667 629  430.11130 6.173291  
##         28) volatile.acidity>=0.465 11   10.72727 4.545455 *
##         29) volatile.acidity< 0.465 618  389.71680 6.202265 *
##       15) alcohol>=11.76667 665  403.99400 6.596992 *
rpart.plot(m.rpart, digits=3)

rpart.plot(m.rpart, digits=4, fallen.leaves = TRUE, type = 3, extra = 101)

Step 4: Evaluating Model Performance

p.rpart <- predict(m.rpart, wine_test)
summary(p.rpart)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   4.545   5.563   5.971   5.893   6.202   6.597
summary(wine_test$quality)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   3.000   5.000   6.000   5.901   6.000   9.000
cor(p.rpart, wine_test$quality)
## [1] 0.5369525

News Popularity

Technique 1

Import the data

news <- read.csv("OnlineNewsPopularity.csv")
str(news)
## 'data.frame':    39644 obs. of  61 variables:
##  $ url                          : Factor w/ 39644 levels "http://mashable.com/2013/01/07/amazon-instant-video-browser/",..: 1 2 3 4 5 6 7 8 9 10 ...
##  $ timedelta                    : num  731 731 731 731 731 731 731 731 731 731 ...
##  $ n_tokens_title               : num  12 9 9 9 13 10 8 12 11 10 ...
##  $ n_tokens_content             : num  219 255 211 531 1072 ...
##  $ n_unique_tokens              : num  0.664 0.605 0.575 0.504 0.416 ...
##  $ n_non_stop_words             : num  1 1 1 1 1 ...
##  $ n_non_stop_unique_tokens     : num  0.815 0.792 0.664 0.666 0.541 ...
##  $ num_hrefs                    : num  4 3 3 9 19 2 21 20 2 4 ...
##  $ num_self_hrefs               : num  2 1 1 0 19 2 20 20 0 1 ...
##  $ num_imgs                     : num  1 1 1 1 20 0 20 20 0 1 ...
##  $ num_videos                   : num  0 0 0 0 0 0 0 0 0 1 ...
##  $ average_token_length         : num  4.68 4.91 4.39 4.4 4.68 ...
##  $ num_keywords                 : num  5 4 6 7 7 9 10 9 7 5 ...
##  $ data_channel_is_lifestyle    : num  0 0 0 0 0 0 1 0 0 0 ...
##  $ data_channel_is_entertainment: num  1 0 0 1 0 0 0 0 0 0 ...
##  $ data_channel_is_bus          : num  0 1 1 0 0 0 0 0 0 0 ...
##  $ data_channel_is_socmed       : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ data_channel_is_tech         : num  0 0 0 0 1 1 0 1 1 0 ...
##  $ data_channel_is_world        : num  0 0 0 0 0 0 0 0 0 1 ...
##  $ kw_min_min                   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ kw_max_min                   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ kw_avg_min                   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ kw_min_max                   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ kw_max_max                   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ kw_avg_max                   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ kw_min_avg                   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ kw_max_avg                   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ kw_avg_avg                   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ self_reference_min_shares    : num  496 0 918 0 545 8500 545 545 0 0 ...
##  $ self_reference_max_shares    : num  496 0 918 0 16000 8500 16000 16000 0 0 ...
##  $ self_reference_avg_sharess   : num  496 0 918 0 3151 ...
##  $ weekday_is_monday            : num  1 1 1 1 1 1 1 1 1 1 ...
##  $ weekday_is_tuesday           : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ weekday_is_wednesday         : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ weekday_is_thursday          : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ weekday_is_friday            : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ weekday_is_saturday          : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ weekday_is_sunday            : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ is_weekend                   : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ LDA_00                       : num  0.5003 0.7998 0.2178 0.0286 0.0286 ...
##  $ LDA_01                       : num  0.3783 0.05 0.0333 0.4193 0.0288 ...
##  $ LDA_02                       : num  0.04 0.0501 0.0334 0.4947 0.0286 ...
##  $ LDA_03                       : num  0.0413 0.0501 0.0333 0.0289 0.0286 ...
##  $ LDA_04                       : num  0.0401 0.05 0.6822 0.0286 0.8854 ...
##  $ global_subjectivity          : num  0.522 0.341 0.702 0.43 0.514 ...
##  $ global_sentiment_polarity    : num  0.0926 0.1489 0.3233 0.1007 0.281 ...
##  $ global_rate_positive_words   : num  0.0457 0.0431 0.0569 0.0414 0.0746 ...
##  $ global_rate_negative_words   : num  0.0137 0.01569 0.00948 0.02072 0.01213 ...
##  $ rate_positive_words          : num  0.769 0.733 0.857 0.667 0.86 ...
##  $ rate_negative_words          : num  0.231 0.267 0.143 0.333 0.14 ...
##  $ avg_positive_polarity        : num  0.379 0.287 0.496 0.386 0.411 ...
##  $ min_positive_polarity        : num  0.1 0.0333 0.1 0.1364 0.0333 ...
##  $ max_positive_polarity        : num  0.7 0.7 1 0.8 1 0.6 1 1 0.8 0.5 ...
##  $ avg_negative_polarity        : num  -0.35 -0.119 -0.467 -0.37 -0.22 ...
##  $ min_negative_polarity        : num  -0.6 -0.125 -0.8 -0.6 -0.5 -0.4 -0.5 -0.5 -0.125 -0.5 ...
##  $ max_negative_polarity        : num  -0.2 -0.1 -0.133 -0.167 -0.05 ...
##  $ title_subjectivity           : num  0.5 0 0 0 0.455 ...
##  $ title_sentiment_polarity     : num  -0.188 0 0 0 0.136 ...
##  $ abs_title_subjectivity       : num  0 0.5 0.5 0.5 0.0455 ...
##  $ abs_title_sentiment_polarity : num  0.188 0 0 0 0.136 ...
##  $ shares                       : int  593 711 1500 1200 505 855 556 891 3600 710 ...
newsShort <- data.frame(news$n_tokens_title, news$n_tokens_content, news$n_unique_tokens, news$n_non_stop_words, news$num_hrefs, news$num_imgs, news$num_videos, news$average_token_length, news$num_keywords, news$kw_max_max, news$global_sentiment_polarity, news$avg_positive_polarity, news$title_subjectivity, news$title_sentiment_polarity, news$abs_title_subjectivity, news$abs_title_sentiment_polarity, news$shares)
colnames(newsShort) <- c("n_tokens_title", "n_tokens_content", "n_unique_tokens", "n_non_stop_words", "num_hrefs", "num_imgs", "num_videos", "average_token_length", "num_keywords", "kw_max_max", "global_sentiment_polarity", "avg_positive_polarity", "title_subjectivity", "title_sentiment_polarity", "abs_title_subjectivity", "abs_title_sentiment_polarity", "shares")

Pre-processing

newsShort$popular = rep('na', nrow(newsShort))
for(i in 1:39644) {
     if(newsShort$shares[i] >= 1400) {
         newsShort$popular[i] = "yes"} 
     else {newsShort$popular[i] = "no"}
}
newsShort$shares = newsShort$popular
newsShort$shares <- as.factor(newsShort$shares)
newsShort <- subset( newsShort, select = -popular )
set.seed(12345)
news_rand <- newsShort[order(runif(49000)), ]
news_train <- news_rand[1:44000, ]
news_test <- news_rand[44001:49000, ]
prop.table(table(news_train$shares))
## 
##        no       yes 
## 0.4662568 0.5337432
prop.table(table(news_test$shares))
## 
##        no       yes 
## 0.4676778 0.5323222

Model training

library(C50)
news_model <- C5.0(news_train[-17], news_train$shares)
summary(news_model)
## 
## Call:
## C5.0.default(x = news_train[-17], y = news_train$shares)
## 
## 
## C5.0 [Release 2.07 GPL Edition]      Sun Jul  1 01:34:44 2018
## -------------------------------
## 
## Class specified by attribute `outcome'
## *** ignoring cases with bad or unknown class
## 
## Read 35622 cases (17 attributes) from undefined.data
## 
## Decision tree:
## 
## num_imgs > 3:
## :...kw_max_max <= 15000:
## :   :...n_tokens_content <= 1111: no (20/2)
## :   :   n_tokens_content > 1111: yes (7/2)
## :   kw_max_max > 15000:
## :   :...num_keywords <= 5:
## :       :...n_unique_tokens > 0.5483304:
## :       :   :...num_videos > 0:
## :       :   :   :...kw_max_max <= 310800: no (8/3)
## :       :   :   :   kw_max_max > 310800: yes (87/21)
## :       :   :   num_videos <= 0:
## :       :   :   :...average_token_length > 5.22907: yes (13)
## :       :   :       average_token_length <= 5.22907:
## :       :   :       :...global_sentiment_polarity <= 0.04: no (27/8)
## :       :   :           global_sentiment_polarity > 0.04: yes (125/42)
## :       :   n_unique_tokens <= 0.5483304:
## :       :   :...n_tokens_title > 9:
## :       :       :...kw_max_max <= 690400: yes (78/33)
## :       :       :   kw_max_max > 690400: no (545/228)
## :       :       n_tokens_title <= 9:
## :       :       :...num_videos <= 1: yes (267/108)
## :       :           num_videos > 1:
## :       :           :...num_imgs > 7: no (7)
## :       :               num_imgs <= 7:
## :       :               :...num_videos <= 2: yes (7)
## :       :                   num_videos > 2: no (6/1)
## :       num_keywords > 5:
## :       :...num_hrefs > 17:
## :           :...n_tokens_content > 2691: yes (53/2)
## :           :   n_tokens_content <= 2691:
## :           :   :...n_tokens_content <= 342: yes (661/156)
## :           :       n_tokens_content > 342:
## :           :       :...n_tokens_title > 9:
## :           :           :...num_imgs <= 12:
## :           :           :   :...num_videos <= 6: yes (592/189)
## :           :           :   :   num_videos > 6:
## :           :           :   :   :...n_tokens_title <= 11: yes (15/3)
## :           :           :   :       n_tokens_title > 11: no (28/8)
## :           :           :   num_imgs > 12:
## :           :           :   :...kw_max_max > 310800:
## :           :           :       :...n_tokens_title <= 13: yes (716/287)
## :           :           :       :   n_tokens_title > 13: no (61/28)
## :           :           :       kw_max_max <= 310800:
## :           :           :       :...kw_max_max <= 17100: no (8)
## :           :           :           kw_max_max > 17100:
## :           :           :           :...num_hrefs <= 22: yes (8)
## :           :           :               num_hrefs > 22: no (31/12)
## :           :           n_tokens_title <= 9:
## :           :           :...abs_title_sentiment_polarity <= 0.425:
## :           :               :...num_imgs <= 28: yes (645/187)
## :           :               :   num_imgs > 28:
## :           :               :   :...average_token_length > 4.696252: yes (34/6)
## :           :               :       average_token_length <= 4.696252:
## :           :               :       :...kw_max_max <= 617900: yes (7/2)
## :           :               :           kw_max_max > 617900: no (33/6)
## :           :               abs_title_sentiment_polarity > 0.425:
## :           :               :...n_tokens_content > 457: yes (209/31)
## :           :                   n_tokens_content <= 457:
## :           :                   :...n_tokens_title <= 6: yes (6)
## :           :                       n_tokens_title > 6:
## :           :                       :...kw_max_max <= 690400: no (6)
## :           :                           kw_max_max > 690400:
## :           :                           :...num_keywords > 9: no (12/3)
## :           :                               num_keywords <= 9: [S1]
## :           num_hrefs <= 17:
## :           :...title_sentiment_polarity > 0.4: yes (658/198)
## :               title_sentiment_polarity <= 0.4:
## :               :...kw_max_max <= 617900: yes (479/157)
## :                   kw_max_max > 617900:
## :                   :...n_tokens_title > 10:
## :                       :...num_hrefs > 6: yes (1088/444)
## :                       :   num_hrefs <= 6:
## :                       :   :...num_videos <= 0: no (503/235)
## :                       :       num_videos > 0:
## :                       :       :...n_unique_tokens <= 0.3534247: yes (37/3)
## :                       :           n_unique_tokens > 0.3534247:
## :                       :           :...avg_positive_polarity > 0.3814904: yes (127/35)
## :                       :               avg_positive_polarity <= 0.3814904:
## :                       :               :...num_hrefs <= 5: no (142/60)
## :                       :                   num_hrefs > 5: [S2]
## :                       n_tokens_title <= 10:
## :                       :...global_sentiment_polarity > 0.09483681: yes (1135/393)
## :                           global_sentiment_polarity <= 0.09483681:
## :                           :...n_tokens_content > 1575:
## :                               :...title_sentiment_polarity <= -0.1461111: yes (4/1)
## :                               :   title_sentiment_polarity > -0.1461111: no (26/1)
## :                               n_tokens_content <= 1575:
## :                               :...kw_max_max <= 690400:
## :                                   :...n_tokens_title > 7: no (32/9)
## :                                   :   n_tokens_title <= 7: [S3]
## :                                   kw_max_max > 690400:
## :                                   :...num_imgs > 6: yes (520/196)
## :                                       num_imgs <= 6:
## :                                       :...num_hrefs <= 9:
## :                                           :...num_videos > 1: no (6)
## :                                           :   num_videos <= 1: [S4]
## :                                           num_hrefs > 9: [S5]
## num_imgs <= 3:
## :...n_unique_tokens > 0.4304388:
##     :...kw_max_max <= 617900:
##     :   :...n_tokens_content > 1204: yes (37/4)
##     :   :   n_tokens_content <= 1204:
##     :   :   :...kw_max_max > 69100: yes (1747/638)
##     :   :       kw_max_max <= 69100:
##     :   :       :...kw_max_max <= 41600: no (374/170)
##     :   :           kw_max_max > 41600: yes (1411/638)
##     :   kw_max_max > 617900:
##     :   :...global_sentiment_polarity <= 0.08261218:
##     :       :...num_imgs <= 0:
##     :       :   :...num_videos > 25:
##     :       :   :   :...num_hrefs <= 52: no (71/18)
##     :       :   :   :   num_hrefs > 52: yes (4)
##     :       :   :   num_videos <= 25:
##     :       :   :   :...kw_max_max <= 690400: yes (250/107)
##     :       :   :       kw_max_max > 690400:
##     :       :   :       :...num_videos > 15: yes (103/37)
##     :       :   :           num_videos <= 15:
##     :       :   :           :...num_keywords <= 6: no (360/141)
##     :       :   :               num_keywords > 6: yes (596/292)
##     :       :   num_imgs > 0:
##     :       :   :...n_unique_tokens > 0.7682927:
##     :       :       :...title_sentiment_polarity <= -0.3: no (3)
##     :       :       :   title_sentiment_polarity > -0.3: yes (45/13)
##     :       :       n_unique_tokens <= 0.7682927:
##     :       :       :...num_hrefs <= 1:
##     :       :           :...kw_max_max > 690400: no (163/26)
##     :       :           :   kw_max_max <= 690400:
##     :       :           :   :...num_keywords > 6: yes (3)
##     :       :           :       num_keywords <= 6:
##     :       :           :       :...num_keywords <= 5: yes (5/1)
##     :       :           :           num_keywords > 5: no (7)
##     :       :           num_hrefs > 1:
##     :       :           :...num_hrefs > 20:
##     :       :               :...num_keywords <= 6: no (150/64)
##     :       :               :   num_keywords > 6: yes (212/91)
##     :       :               num_hrefs <= 20:
##     :       :               :...average_token_length > 4.747073:
##     :       :                   :...num_hrefs > 4:
##     :       :                   :   :...n_tokens_content <= 164: yes (32/7)
##     :       :                   :   :   n_tokens_content > 164: no (2129/730)
##     :       :                   :   num_hrefs <= 4:
##     :       :                   :   :...kw_max_max <= 690400:
##     :       :                   :       :...n_tokens_title <= 9: no (22/7)
##     :       :                   :       :   n_tokens_title > 9: yes (21/5)
##     :       :                   :       kw_max_max > 690400:
##     :       :                   :       :...num_imgs <= 2: no (435/110)
##     :       :                   :           num_imgs > 2:
##     :       :                   :           :...n_unique_tokens <= 0.4491979: yes (4)
##     :       :                   :               n_unique_tokens > 0.4491979: no (30/10)
##     :       :                   average_token_length <= 4.747073:
##     :       :                   :...num_imgs > 2:
##     :       :                       :...num_hrefs <= 3:
##     :       :                       :   :...n_unique_tokens > 0.6126984: yes (3)
##     :       :                       :   :   n_unique_tokens <= 0.6126984: [S6]
##     :       :                       :   num_hrefs > 3:
##     :       :                       :   :...num_keywords > 6: yes (64/16)
##     :       :                       :       num_keywords <= 6: [S7]
##     :       :                       num_imgs <= 2:
##     :       :                       :...num_keywords <= 5: no (750/284)
##     :       :                           num_keywords > 5:
##     :       :                           :...num_imgs <= 1: no (1317/581)
##     :       :                               num_imgs > 1: [S8]
##     :       global_sentiment_polarity > 0.08261218:
##     :       :...num_hrefs > 15:
##     :           :...n_tokens_title <= 9: yes (582/189)
##     :           :   n_tokens_title > 9:
##     :           :   :...abs_title_subjectivity > 0.09583333: yes (748/329)
##     :           :       abs_title_subjectivity <= 0.09583333:
##     :           :       :...num_imgs <= 0: yes (43/18)
##     :           :           num_imgs > 0:
##     :           :           :...num_keywords <= 5: no (36/6)
##     :           :               num_keywords > 5:
##     :           :               :...num_videos > 0: no (46/11)
##     :           :                   num_videos <= 0:
##     :           :                   :...num_imgs > 1: yes (4)
##     :           :                       num_imgs <= 1: [S9]
##     :           num_hrefs <= 15:
##     :           :...num_imgs > 1:
##     :               :...n_unique_tokens > 0.6486486:
##     :               :   :...global_sentiment_polarity <= 0.3318182: yes (159/35)
##     :               :   :   global_sentiment_polarity > 0.3318182: no (10/2)
##     :               :   n_unique_tokens <= 0.6486486:
##     :               :   :...num_keywords <= 9: yes (1404/654)
##     :               :       num_keywords > 9:
##     :               :       :...num_videos > 1: yes (17/3)
##     :               :           num_videos <= 1:
##     :               :           :...num_videos <= 0:
##     :               :               :...num_hrefs <= 8: yes (74/20)
##     :               :               :   num_hrefs > 8: [S10]
##     :               :               num_videos > 0:
##     :               :               :...avg_positive_polarity <= 0.3091198: yes (19/5)
##     :               :                   avg_positive_polarity > 0.3091198:
##     :               :                   :...num_hrefs > 9: yes (20/1)
##     :               :                       num_hrefs <= 9:
##     :               :                       :...num_hrefs <= 6: no (14/2)
##     :               :                           num_hrefs > 6: yes (22/10)
##     :               num_imgs <= 1:
##     :               :...num_videos > 0:
##     :                   :...kw_max_max <= 690400:
##     :                   :   :...num_imgs <= 0:
##     :                   :   :   :...num_keywords <= 7:
##     :                   :   :   :   :...n_tokens_title <= 7: no (19/8)
##     :                   :   :   :   :   n_tokens_title > 7: yes (212/66)
##     :                   :   :   :   num_keywords > 7:
##     :                   :   :   :   :...n_unique_tokens <= 0.6703297: no (61/24)
##     :                   :   :   :       n_unique_tokens > 0.6703297: yes (22/4)
##     :                   :   :   num_imgs > 0:
##     :                   :   :   :...average_token_length <= 4.39404: yes (29/4)
##     :                   :   :       average_token_length > 4.39404:
##     :                   :   :       :...num_hrefs > 9: yes (44/13)
##     :                   :   :           num_hrefs <= 9:
##     :                   :   :           :...num_videos > 3: yes (12/3)
##     :                   :   :               num_videos <= 3:
##     :                   :   :               :...num_keywords > 6: no (69/17)
##     :                   :   :                   num_keywords <= 6: [S11]
##     :                   :   kw_max_max > 690400:
##     :                   :   :...num_videos > 10: yes (191/71)
##     :                   :       num_videos <= 10:
##     :                   :       :...n_tokens_title <= 9: no (771/370)
##     :                   :           n_tokens_title > 9:
##     :                   :           :...num_hrefs <= 9: yes (1684/755)
##     :                   :               num_hrefs > 9:
##     :                   :               :...num_keywords <= 8:
##     :                   :                   :...num_keywords <= 5: [S12]
##     :                   :                   :   num_keywords > 5: [S13]
##     :                   :                   num_keywords > 8:
##     :                   :                   :...num_imgs <= 0: no (44/19)
##     :                   :                       num_imgs > 0: [S14]
##     :                   num_videos <= 0:
##     :                   :...n_tokens_content > 668: yes (759/324)
##     :                       n_tokens_content <= 668:
##     :                       :...title_sentiment_polarity > -0.008333334:
##     :                           :...num_imgs > 0:
##     :                           :   :...n_tokens_content <= 121: yes (101/36)
##     :                           :   :   n_tokens_content > 121: no (4008/1746)
##     :                           :   num_imgs <= 0:
##     :                           :   :...n_tokens_content > 141:
##     :                           :       :...num_keywords <= 5: no (73/31)
##     :                           :       :   num_keywords > 5: yes (411/158)
##     :                           :       n_tokens_content <= 141:
##     :                           :       :...n_tokens_title > 9:
##     :                           :           :...n_unique_tokens <= 0.8265306: no (104/21)
##     :                           :           :   n_unique_tokens > 0.8265306: yes (8/1)
##     :                           :           n_tokens_title <= 9:
##     :                           :           :...kw_max_max <= 690400: yes (35/10)
##     :                           :               kw_max_max > 690400: [S15]
##     :                           title_sentiment_polarity <= -0.008333334:
##     :                           :...n_unique_tokens > 0.71875:
##     :                               :...n_tokens_title > 12: no (89/3)
##     :                               :   n_tokens_title <= 12:
##     :                               :   :...n_unique_tokens <= 0.7894737: no (69/11)
##     :                               :       n_unique_tokens > 0.7894737: yes (14/5)
##     :                               n_unique_tokens <= 0.71875:
##     :                               :...n_tokens_title > 12: no (89/25)
##     :                                   n_tokens_title <= 12:
##     :                                   :...num_imgs > 0: no (303/124)
##     :                                       num_imgs <= 0: [S16]
##     n_unique_tokens <= 0.4304388:
##     :...num_hrefs > 19: yes (387/93)
##         num_hrefs <= 19:
##         :...num_videos > 8:
##             :...num_keywords <= 8: no (40/10)
##             :   num_keywords > 8:
##             :   :...average_token_length <= 4.819527: yes (8)
##             :       average_token_length > 4.819527: no (2)
##             num_videos <= 8:
##             :...kw_max_max <= 663600: yes (180/46)
##                 kw_max_max > 663600:
##                 :...global_sentiment_polarity > 0.154227: yes (399/112)
##                     global_sentiment_polarity <= 0.154227:
##                     :...average_token_length > 4.729216:
##                         :...num_videos <= 1:
##                         :   :...num_hrefs <= 14: no (166/50)
##                         :   :   num_hrefs > 14:
##                         :   :   :...global_sentiment_polarity <= 0.1335317: no (40/19)
##                         :   :       global_sentiment_polarity > 0.1335317: yes (9)
##                         :   num_videos > 1:
##                         :   :...title_sentiment_polarity <= -0.1402778: no (5)
##                         :       title_sentiment_polarity > -0.1402778:
##                         :       :...avg_positive_polarity <= 0.2935334: no (5/1)
##                         :           avg_positive_polarity > 0.2935334: yes (19/3)
##                         average_token_length <= 4.729216:
##                         :...num_imgs > 2: yes (99/32)
##                             num_imgs <= 2:
##                             :...kw_max_max <= 690400: yes (85/34)
##                                 kw_max_max > 690400:
##                                 :...num_hrefs > 15: no (55/22)
##                                     num_hrefs <= 15:
##                                     :...num_hrefs > 10: yes (138/39)
##                                         num_hrefs <= 10:
##                                         :...n_tokens_content > 1113:
##                                             :...n_unique_tokens > 0.4021739: no (50/12)
##                                             :   n_unique_tokens <= 0.4021739:
##                                             :   :...num_videos > 2: no (4)
##                                             :       num_videos <= 2: [S17]
##                                             n_tokens_content <= 1113:
##                                             :...num_imgs > 1: yes (37/10)
##                                                 num_imgs <= 1:
##                                                 :...num_imgs > 0: [S18]
##                                                     num_imgs <= 0: [S19]
## 
## SubTree [S1]
## 
## n_tokens_content <= 422: yes (15/1)
## n_tokens_content > 422: no (7/2)
## 
## SubTree [S2]
## 
## title_sentiment_polarity <= -0.325: no (4)
## title_sentiment_polarity > -0.325: yes (38/12)
## 
## SubTree [S3]
## 
## global_sentiment_polarity <= 0.02484504: no (4/1)
## global_sentiment_polarity > 0.02484504: yes (7)
## 
## SubTree [S4]
## 
## n_tokens_content <= 436: yes (27/10)
## n_tokens_content > 436: no (66/15)
## 
## SubTree [S5]
## 
## average_token_length > 5.011019: no (5)
## average_token_length <= 5.011019:
## :...num_videos <= 3: yes (52/14)
##     num_videos > 3: no (5/1)
## 
## SubTree [S6]
## 
## global_sentiment_polarity <= 0.06216631: no (19/1)
## global_sentiment_polarity > 0.06216631:
## :...global_sentiment_polarity <= 0.07848307: yes (5)
##     global_sentiment_polarity > 0.07848307: no (3)
## 
## SubTree [S7]
## 
## average_token_length <= 4.407609: yes (6)
## average_token_length > 4.407609:
## :...n_tokens_title <= 14: no (48/19)
##     n_tokens_title > 14: yes (3)
## 
## SubTree [S8]
## 
## n_tokens_content <= 623: yes (216/101)
## n_tokens_content > 623:
## :...avg_positive_polarity <= 0.3597222: no (59/9)
##     avg_positive_polarity > 0.3597222:
##     :...num_keywords > 9: yes (4)
##         num_keywords <= 9:
##         :...global_sentiment_polarity <= 0.07012397: no (18/5)
##             global_sentiment_polarity > 0.07012397: yes (5)
## 
## SubTree [S9]
## 
## abs_title_subjectivity > 0.01136364: no (23/9)
## abs_title_subjectivity <= 0.01136364:
## :...avg_positive_polarity <= 0.2931903: no (2)
##     avg_positive_polarity > 0.2931903: yes (18/3)
## 
## SubTree [S10]
## 
## abs_title_subjectivity <= 0.4125: yes (28/8)
## abs_title_subjectivity > 0.4125: no (28/9)
## 
## SubTree [S11]
## 
## global_sentiment_polarity <= 0.2202445: no (35/16)
## global_sentiment_polarity > 0.2202445: yes (6)
## 
## SubTree [S12]
## 
## global_sentiment_polarity <= 0.2365167: no (43/14)
## global_sentiment_polarity > 0.2365167: yes (4)
## 
## SubTree [S13]
## 
## abs_title_sentiment_polarity <= 0.7: no (152/58)
## abs_title_sentiment_polarity > 0.7: yes (8/3)
## 
## SubTree [S14]
## 
## average_token_length > 4.955523: no (13/2)
## average_token_length <= 4.955523:
## :...num_videos <= 9: yes (71/20)
##     num_videos > 9: no (5/1)
## 
## SubTree [S15]
## 
## n_tokens_content <= 96: no (19/4)
## n_tokens_content > 96:
## :...title_subjectivity <= 0.6625: yes (10)
##     title_subjectivity > 0.6625: no (4/1)
## 
## SubTree [S16]
## 
## abs_title_subjectivity > 0.425: no (5)
## abs_title_subjectivity <= 0.425:
## :...n_tokens_title > 10: yes (23/4)
##     n_tokens_title <= 10:
##     :...n_tokens_title <= 9: yes (12/3)
##         n_tokens_title > 9:
##         :...n_tokens_content <= 168: yes (2)
##             n_tokens_content > 168: no (8)
## 
## SubTree [S17]
## 
## global_sentiment_polarity <= 0.1441667: yes (66/25)
## global_sentiment_polarity > 0.1441667: no (7)
## 
## SubTree [S18]
## 
## n_non_stop_words <= 0: yes (63/19)
## n_non_stop_words > 0:
## :...global_sentiment_polarity <= 0.02890873: no (8/1)
##     global_sentiment_polarity > 0.02890873:
##     :...n_unique_tokens <= 0.3853428: yes (18/1)
##         n_unique_tokens > 0.3853428:
##         :...num_hrefs <= 5: no (27/8)
##             num_hrefs > 5: yes (54/19)
## 
## SubTree [S19]
## 
## n_tokens_title > 14: no (28/10)
## n_tokens_title <= 14:
## :...num_videos > 0: yes (602/253)
##     num_videos <= 0:
##     :...n_tokens_title > 13: yes (5)
##         n_tokens_title <= 13:
##         :...num_keywords <= 7: no (15/1)
##             num_keywords > 7:
##             :...num_keywords <= 9: yes (14/3)
##                 num_keywords > 9:
##                 :...abs_title_subjectivity <= 0.09415584: yes (2)
##                     abs_title_subjectivity > 0.09415584: no (4)
## 
## 
## Evaluation on training data (35622 cases):
## 
##      Decision Tree   
##    ----------------  
##    Size      Errors  
## 
##     190 13393(37.6%)   <<
## 
## 
##     (a)   (b)    <-classified as
##    ----  ----
##    8682  7927    (a): class no
##    5466 13547    (b): class yes
## 
## 
##  Attribute usage:
## 
##  100.00% num_imgs
##   98.77% kw_max_max
##   82.81% num_hrefs
##   78.13% n_unique_tokens
##   67.85% global_sentiment_polarity
##   48.03% n_tokens_content
##   45.46% num_keywords
##   44.31% num_videos
##   37.22% n_tokens_title
##   29.28% title_sentiment_polarity
##   20.81% average_token_length
##    3.18% abs_title_sentiment_polarity
##    2.90% abs_title_subjectivity
##    1.45% avg_positive_polarity
##    0.48% n_non_stop_words
##    0.04% title_subjectivity
## 
## 
## Time: 0.5 secs

Evaluate the Model

news_pred <- predict(news_model, news_test)
(p <- table(news_pred, news_test$shares))
##          
## news_pred   no  yes
##       no   867  674
##       yes 1014 1467
(Accuracy <- sum(diag(p))/sum(p)*100)
## [1] 58.03083

Technique 2

Model training

library(kernlab)
news_model2 <- ksvm(shares ~ ., data = news_train, kernel = "vanilladot")
##  Setting default kernel parameters
summary(news_model2)
## Length  Class   Mode 
##      1   ksvm     S4

Evaluate the Model

news_pred2 <- predict(news_model2, news_test)
#####(p <- table(news_pred2, news_test$shares))
#####I'm not sure why I keep seeing the error "all arguments must have the same length"

Technique 3

Model training

library(rpart)
m.rpart <- rpart(shares ~ ., data=news_train)
summary(m.rpart)
## Call:
## rpart(formula = shares ~ ., data = news_train)
##   n=35622 (8378 observations deleted due to missingness)
## 
##           CP nsplit rel error    xerror        xstd
## 1 0.03251249      0 1.0000000 1.0000000 0.005668843
## 2 0.01216208      2 0.9349750 0.9400325 0.005638366
## 3 0.01000000      3 0.9228129 0.9347944 0.005634845
## 
## Variable importance
##                  num_imgs global_sentiment_polarity 
##                        44                        22 
##                kw_max_max     avg_positive_polarity 
##                        11                         6 
##                 num_hrefs          n_non_stop_words 
##                         5                         5 
##          n_tokens_content      average_token_length 
##                         4                         2 
##           n_unique_tokens 
##                         2 
## 
## Node number 1: 35622 observations,    complexity param=0.03251249
##   predicted class=yes  expected loss=0.4662568  P(node) =1
##     class counts: 16609 19013
##    probabilities: 0.466 0.534 
##   left son=2 (26313 obs) right son=3 (9309 obs)
##   Primary splits:
##       num_imgs                  < 3.5        to the left,  improve=204.43790, (0 missing)
##       num_hrefs                 < 13.5       to the left,  improve=163.26770, (0 missing)
##       global_sentiment_polarity < 0.09269021 to the left,  improve=130.72360, (0 missing)
##       n_unique_tokens           < 0.4396835  to the right, improve= 90.54954, (0 missing)
##       num_keywords              < 6.5        to the left,  improve= 78.65559, (0 missing)
##   Surrogate splits:
##       num_hrefs                 < 18.5       to the left,  agree=0.768, adj=0.114, (0 split)
##       n_non_stop_words          < 1          to the left,  agree=0.757, adj=0.070, (0 split)
##       n_tokens_content          < 1339.5     to the left,  agree=0.753, adj=0.057, (0 split)
##       global_sentiment_polarity < -0.1855226 to the right, agree=0.740, adj=0.004, (0 split)
##       average_token_length      < 5.626769   to the left,  agree=0.740, adj=0.004, (0 split)
## 
## Node number 2: 26313 observations,    complexity param=0.03251249
##   predicted class=yes  expected loss=0.4981188  P(node) =0.7386727
##     class counts: 13107 13206
##    probabilities: 0.498 0.502 
##   left son=4 (10534 obs) right son=5 (15779 obs)
##   Primary splits:
##       global_sentiment_polarity < 0.09269021 to the left,  improve=99.22453, (0 missing)
##       n_unique_tokens           < 0.4304826  to the right, improve=78.06604, (0 missing)
##       kw_max_max                < 677000     to the right, improve=76.51894, (0 missing)
##       num_hrefs                 < 19.5       to the left,  improve=56.02928, (0 missing)
##       average_token_length      < 4.781043   to the right, improve=54.85230, (0 missing)
##   Surrogate splits:
##       avg_positive_polarity < 0.3012278  to the left,  agree=0.702, adj=0.256, (0 split)
##       n_unique_tokens       < 0.1845133  to the left,  agree=0.630, adj=0.077, (0 split)
##       average_token_length  < 3.659021   to the left,  agree=0.630, adj=0.077, (0 split)
##       n_tokens_content      < 9          to the left,  agree=0.630, adj=0.077, (0 split)
##       n_non_stop_words      < 0.5        to the left,  agree=0.630, adj=0.077, (0 split)
## 
## Node number 3: 9309 observations
##   predicted class=yes  expected loss=0.3761951  P(node) =0.2613273
##     class counts:  3502  5807
##    probabilities: 0.376 0.624 
## 
## Node number 4: 10534 observations,    complexity param=0.01216208
##   predicted class=no   expected loss=0.4487374  P(node) =0.2957161
##     class counts:  5807  4727
##    probabilities: 0.551 0.449 
##   left son=8 (9288 obs) right son=9 (1246 obs)
##   Primary splits:
##       kw_max_max           < 654150     to the right, improve=49.48608, (0 missing)
##       n_non_stop_words     < 1          to the right, improve=48.04450, (0 missing)
##       n_tokens_content     < 161.5      to the right, improve=47.03210, (0 missing)
##       num_imgs             < 0.5        to the right, improve=45.60699, (0 missing)
##       average_token_length < 4.729654   to the right, improve=45.30676, (0 missing)
##   Surrogate splits:
##       n_unique_tokens < 0.9755102  to the left,  agree=0.882, adj=0.002, (0 split)
## 
## Node number 5: 15779 observations
##   predicted class=yes  expected loss=0.4626402  P(node) =0.4429566
##     class counts:  7300  8479
##    probabilities: 0.463 0.537 
## 
## Node number 8: 9288 observations
##   predicted class=no   expected loss=0.4309862  P(node) =0.2607377
##     class counts:  5285  4003
##    probabilities: 0.569 0.431 
## 
## Node number 9: 1246 observations
##   predicted class=yes  expected loss=0.4189406  P(node) =0.03497838
##     class counts:   522   724
##    probabilities: 0.419 0.581

Visualization

library(rpart.plot)
rpart.plot(m.rpart, digits=3, type=1)

Evaluate the Model

p.rpart <- predict(m.rpart, news_test)
summary(p.rpart) 
##        no              yes        
##  Min.   :0.3762   Min.   :0.4310  
##  1st Qu.:0.4626   1st Qu.:0.5374  
##  Median :0.4626   Median :0.5374  
##  Mean   :0.4659   Mean   :0.5341  
##  3rd Qu.:0.4626   3rd Qu.:0.5374  
##  Max.   :0.5690   Max.   :0.6238
summary(news_test$shares) 
##   no  yes NA's 
## 1881 2141  978