Method 1. Tree-based classification

credit <- read.csv("C:/Users/zeemo/Desktop/Files/Data/RStudio/credit.csv", header=TRUE) 
str(credit)

‘data.frame’: 1000 obs. of 21 variables: $ Creditability : int 1 1 1 1 1 1 1 1 1 1 … $ Account.Balance : int 1 1 2 1 1 1 1 1 4 2 … $ Duration.of.Credit..month. : int 18 9 12 12 12 10 8 6 18 24 … $ Payment.Status.of.Previous.Credit: int 4 4 2 4 4 4 4 4 4 2 … $ Purpose : int 2 0 9 0 0 0 0 0 3 3 … $ Credit.Amount : int 1049 2799 841 2122 2171 2241 3398 1361 1098 3758 … $ Value.Savings.Stocks : int 1 1 2 1 1 1 1 1 1 3 … $ Length.of.current.employment : int 2 3 4 3 3 2 4 2 1 1 … $ Instalment.per.cent : int 4 2 2 3 4 1 1 2 4 1 … $ Sex…Marital.Status : int 2 3 2 3 3 3 3 3 2 2 … $ Guarantors : int 1 1 1 1 1 1 1 1 1 1 … $ Duration.in.Current.address : int 4 2 4 2 4 3 4 4 4 4 … $ Most.valuable.available.asset : int 2 1 1 1 2 1 1 1 3 4 … $ Age..years. : int 21 36 23 39 38 48 39 40 65 23 … $ Concurrent.Credits : int 3 3 3 3 1 3 3 3 3 3 … $ Type.of.apartment : int 1 1 1 1 2 1 2 2 2 1 … $ No.of.Credits.at.this.Bank : int 1 2 1 2 2 2 2 1 2 1 … $ Occupation : int 3 3 2 2 2 2 2 2 1 1 … $ No.of.dependents : int 1 2 1 2 1 2 1 2 1 1 … $ Telephone : int 1 1 1 1 1 1 1 1 1 1 … $ Foreign.Worker : int 1 1 1 2 2 2 2 2 1 1 …

Step 2: Exploring the data

summary(credit$amount)
## Length  Class   Mode 
##      0   NULL   NULL
table(credit$Creditability)
## 
##   0   1 
## 300 700
set.seed(12345)
credit_rand <- credit[order(runif(1000)), ]
summary(credit$Credit.Amount)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##     250    1366    2320    3271    3972   18424
credit_train <-credit_rand[1:900, ]
credit_test <-credit_rand[901:1000, ]
prop.table(table(credit_train$Creditability))
## 
##         0         1 
## 0.3088889 0.6911111
prop.table(table(credit_test$Creditability))
## 
##    0    1 
## 0.22 0.78

##Step 3: Training a model on the data

library(C50)
## Warning: package 'C50' was built under R version 3.6.3
credit_train$Creditability <- as.factor(credit_train$Creditability)
credit_test$Creditability <- as.factor(credit_test$Creditability)
credit_model <- C5.0(x = credit_train[-1], y = credit_train$Creditability)
credit_model
## 
## Call:
## C5.0.default(x = credit_train[-1], y = credit_train$Creditability)
## 
## Classification Tree
## Number of samples: 900 
## Number of predictors: 20 
## 
## Tree size: 85 
## 
## Non-standard options: attempt to group attributes

##Step 4: Evaluating Model Performance

cred_pred <- predict(credit_model, credit_test)
if (!require("gmodels")) {
  install.packages("gmodels")
  library(gmodels)
}
## Loading required package: gmodels
## Warning: package 'gmodels' was built under R version 3.6.3
CrossTable(credit_test$Creditability, cred_pred, prop.chisq = FALSE, prop.c = FALSE, prop.r = FALSE, dnn = c('Actual Creditability', 'Predicted Creditability'))
## 
##  
##    Cell Contents
## |-------------------------|
## |                       N |
## |         N / Table Total |
## |-------------------------|
## 
##  
## Total Observations in Table:  100 
## 
##  
##                      | Predicted Creditability 
## Actual Creditability |         0 |         1 | Row Total | 
## ---------------------|-----------|-----------|-----------|
##                    0 |         8 |        14 |        22 | 
##                      |     0.080 |     0.140 |           | 
## ---------------------|-----------|-----------|-----------|
##                    1 |        17 |        61 |        78 | 
##                      |     0.170 |     0.610 |           | 
## ---------------------|-----------|-----------|-----------|
##         Column Total |        25 |        75 |       100 | 
## ---------------------|-----------|-----------|-----------|
## 
## 
(p <- table(cred_pred, credit_test$Creditability))
##          
## cred_pred  0  1
##         0  8 17
##         1 14 61
(Accuracy <- sum(diag(p))/sum(p)*100)
## [1] 69

#Q1 ### It does not mean 100% has a perfect model, however, it does indicate that the model fit well. However, in case to avoide the situation of overmatch, we need further tests or other parameters.

Method 2

if (!require("randomForest")) {
  install.packages("randomForest")
  library(randomForest)
}
## Loading required package: randomForest
## Warning: package 'randomForest' was built under R version 3.6.3
## randomForest 4.6-14
## Type rfNews() to see new features/changes/bug fixes.
credit_train$Creditability <-as.factor(credit_train$Creditability) 
random_model <-randomForest(Creditability ~ . , data= credit_train)
summary(random_model)
##                 Length Class  Mode     
## call               3   -none- call     
## type               1   -none- character
## predicted        900   factor numeric  
## err.rate        1500   -none- numeric  
## confusion          6   -none- numeric  
## votes           1800   matrix numeric  
## oob.times        900   -none- numeric  
## classes            2   -none- character
## importance        20   -none- numeric  
## importanceSD       0   -none- NULL     
## localImportance    0   -none- NULL     
## proximity          0   -none- NULL     
## ntree              1   -none- numeric  
## mtry               1   -none- numeric  
## forest            14   -none- list     
## y                900   factor numeric  
## test               0   -none- NULL     
## inbag              0   -none- NULL     
## terms              3   terms  call
cred_pred <- predict(random_model, credit_test)
(p <- table(cred_pred, credit_test$Creditability))
##          
## cred_pred  0  1
##         0 11 10
##         1 11 68
(Accuracy <- sum(diag(p))/sum(p)*100)
## [1] 79

Q2

Three most imprtant features are Account Balance, Duration of credit and Payment Status.

importance(random_model)
##                                   MeanDecreaseGini
## Account.Balance                          42.599355
## Duration.of.Credit..month.               37.502785
## Payment.Status.of.Previous.Credit        22.563009
## Purpose                                  23.774048
## Credit.Amount                            52.397155
## Value.Savings.Stocks                     19.388385
## Length.of.current.employment             20.221289
## Instalment.per.cent                      16.394636
## Sex...Marital.Status                     13.424449
## Guarantors                                7.475422
## Duration.in.Current.address              15.563685
## Most.valuable.available.asset            17.326842
## Age..years.                              37.377916
## Concurrent.Credits                        8.480725
## Type.of.apartment                         9.595344
## No.of.Credits.at.this.Bank                8.424006
## Occupation                               12.669816
## No.of.dependents                          5.774473
## Telephone                                 7.505291
## Foreign.Worker                            1.746964

Q2 Change to 23458

set.seed(23458)
random_model1 <- randomForest(Creditability ~ (Credit.Amount + Account.Balance + Age..years.), data= credit_train)
cred_pred1 <- predict(random_model1, credit_test)
(p1 <- table(cred_pred1, credit_test$Creditability))
##           
## cred_pred1  0  1
##          0  5  4
##          1 17 74
(Accuracy <- sum(diag(p1))/sum(p1)*100)
## [1] 79

Method 3.Adding regression to trees

wine <- read.csv("C:/Users/zeemo/Desktop/Files/Data/RStudio/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 ...

##check to see if the class variable, quality, follows a normal distribution or is nearly normal.

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

if (!require("rpart")) {
install.packages("rpart")
library(rpart)
}
## Loading required package: rpart
if (!require("rpart.plot")) {
install.packages("rpart.plot")
library(rpart.plot)
}
## Loading required package: rpart.plot
## Warning: package 'rpart.plot' was built under R version 3.6.3
m.rpart <- rpart(quality ~ ., data=wine_train)
summary(m.rpart)
## Call:
## rpart(formula = quality ~ ., data = wine_train)
##   n= 3750 
## 
##           CP nsplit rel error    xerror       xstd
## 1 0.15501053      0 1.0000000 1.0006805 0.02446810
## 2 0.05098911      1 0.8449895 0.8513823 0.02347467
## 3 0.02796998      2 0.7940004 0.8064997 0.02277860
## 4 0.01970128      3 0.7660304 0.7885635 0.02183879
## 5 0.01265926      4 0.7463291 0.7638299 0.02077561
## 6 0.01007193      5 0.7336698 0.7507459 0.02052777
## 7 0.01000000      6 0.7235979 0.7470415 0.02049539
## 
## Variable importance
##              alcohol              density     volatile.acidity 
##                   34                   21                   15 
##            chlorides total.sulfur.dioxide  free.sulfur.dioxide 
##                   11                    7                    6 
##       residual.sugar            sulphates          citric.acid 
##                    3                    1                    1 
## 
## Node number 1: 3750 observations,    complexity param=0.1550105
##   mean=5.870933, MSE=0.7854751 
##   left son=2 (2372 obs) right son=3 (1378 obs)
##   Primary splits:
##       alcohol              < 10.85    to the left,  improve=0.15501050, (0 missing)
##       density              < 0.992035 to the right, improve=0.10915940, (0 missing)
##       chlorides            < 0.0395   to the right, improve=0.07682258, (0 missing)
##       total.sulfur.dioxide < 158.5    to the right, improve=0.04089663, (0 missing)
##       citric.acid          < 0.235    to the left,  improve=0.03636458, (0 missing)
##   Surrogate splits:
##       density              < 0.991995 to the right, agree=0.869, adj=0.644, (0 split)
##       chlorides            < 0.0375   to the right, agree=0.757, adj=0.339, (0 split)
##       total.sulfur.dioxide < 103.5    to the right, agree=0.690, adj=0.155, (0 split)
##       residual.sugar       < 5.375    to the right, agree=0.667, adj=0.094, (0 split)
##       sulphates            < 0.345    to the right, agree=0.647, adj=0.038, (0 split)
## 
## Node number 2: 2372 observations,    complexity param=0.05098911
##   mean=5.604975, MSE=0.5981709 
##   left son=4 (1611 obs) right son=5 (761 obs)
##   Primary splits:
##       volatile.acidity    < 0.2275   to the right, improve=0.10585250, (0 missing)
##       free.sulfur.dioxide < 13.5     to the left,  improve=0.03390500, (0 missing)
##       citric.acid         < 0.235    to the left,  improve=0.03204075, (0 missing)
##       alcohol             < 10.11667 to the left,  improve=0.03136524, (0 missing)
##       chlorides           < 0.0585   to the right, improve=0.01633599, (0 missing)
##   Surrogate splits:
##       pH                   < 3.485    to the left,  agree=0.694, adj=0.047, (0 split)
##       sulphates            < 0.755    to the left,  agree=0.685, adj=0.020, (0 split)
##       total.sulfur.dioxide < 105.5    to the right, agree=0.683, adj=0.011, (0 split)
##       residual.sugar       < 0.75     to the right, agree=0.681, adj=0.007, (0 split)
##       chlorides            < 0.0285   to the right, agree=0.680, adj=0.003, (0 split)
## 
## Node number 3: 1378 observations,    complexity param=0.02796998
##   mean=6.328737, MSE=0.7765472 
##   left son=6 (84 obs) right son=7 (1294 obs)
##   Primary splits:
##       free.sulfur.dioxide  < 10.5     to the left,  improve=0.07699080, (0 missing)
##       alcohol              < 11.76667 to the left,  improve=0.06210660, (0 missing)
##       total.sulfur.dioxide < 67.5     to the left,  improve=0.04438619, (0 missing)
##       residual.sugar       < 1.375    to the left,  improve=0.02905351, (0 missing)
##       fixed.acidity        < 7.35     to the right, improve=0.02613259, (0 missing)
##   Surrogate splits:
##       total.sulfur.dioxide < 53.5     to the left,  agree=0.952, adj=0.214, (0 split)
##       volatile.acidity     < 0.875    to the right, agree=0.940, adj=0.024, (0 split)
## 
## Node number 4: 1611 observations,    complexity param=0.01265926
##   mean=5.43203, MSE=0.5098121 
##   left son=8 (688 obs) right son=9 (923 obs)
##   Primary splits:
##       volatile.acidity    < 0.3025   to the right, improve=0.04540111, (0 missing)
##       alcohol             < 10.05    to the left,  improve=0.03874403, (0 missing)
##       free.sulfur.dioxide < 13.5     to the left,  improve=0.03338886, (0 missing)
##       chlorides           < 0.0495   to the right, improve=0.02574623, (0 missing)
##       citric.acid         < 0.195    to the left,  improve=0.02327981, (0 missing)
##   Surrogate splits:
##       citric.acid          < 0.215    to the left,  agree=0.633, adj=0.141, (0 split)
##       free.sulfur.dioxide  < 20.5     to the left,  agree=0.600, adj=0.063, (0 split)
##       chlorides            < 0.0595   to the right, agree=0.593, adj=0.047, (0 split)
##       residual.sugar       < 1.15     to the left,  agree=0.583, adj=0.023, (0 split)
##       total.sulfur.dioxide < 219.25   to the right, agree=0.582, adj=0.022, (0 split)
## 
## Node number 5: 761 observations
##   mean=5.971091, MSE=0.5878633 
## 
## Node number 6: 84 observations
##   mean=5.369048, MSE=1.137613 
## 
## Node number 7: 1294 observations,    complexity param=0.01970128
##   mean=6.391036, MSE=0.6894405 
##   left son=14 (629 obs) right son=15 (665 obs)
##   Primary splits:
##       alcohol              < 11.76667 to the left,  improve=0.06504696, (0 missing)
##       chlorides            < 0.0395   to the right, improve=0.02758705, (0 missing)
##       fixed.acidity        < 7.35     to the right, improve=0.02750932, (0 missing)
##       pH                   < 3.055    to the left,  improve=0.02307356, (0 missing)
##       total.sulfur.dioxide < 191.5    to the right, improve=0.02186818, (0 missing)
##   Surrogate splits:
##       density              < 0.990885 to the right, agree=0.720, adj=0.424, (0 split)
##       volatile.acidity     < 0.2675   to the left,  agree=0.637, adj=0.253, (0 split)
##       chlorides            < 0.0365   to the right, agree=0.630, adj=0.238, (0 split)
##       residual.sugar       < 1.475    to the left,  agree=0.575, adj=0.126, (0 split)
##       total.sulfur.dioxide < 128.5    to the right, agree=0.574, adj=0.124, (0 split)
## 
## Node number 8: 688 observations
##   mean=5.255814, MSE=0.4054895 
## 
## Node number 9: 923 observations
##   mean=5.56338, MSE=0.5471747 
## 
## Node number 14: 629 observations,    complexity param=0.01007193
##   mean=6.173291, MSE=0.6838017 
##   left son=28 (11 obs) right son=29 (618 obs)
##   Primary splits:
##       volatile.acidity     < 0.465    to the right, improve=0.06897561, (0 missing)
##       total.sulfur.dioxide < 200      to the right, improve=0.04223066, (0 missing)
##       residual.sugar       < 0.975    to the left,  improve=0.03061714, (0 missing)
##       fixed.acidity        < 7.35     to the right, improve=0.02978501, (0 missing)
##       sulphates            < 0.575    to the left,  improve=0.02165970, (0 missing)
##   Surrogate splits:
##       citric.acid          < 0.045    to the left,  agree=0.986, adj=0.182, (0 split)
##       total.sulfur.dioxide < 279.25   to the right, agree=0.986, adj=0.182, (0 split)
## 
## Node number 15: 665 observations
##   mean=6.596992, MSE=0.6075098 
## 
## Node number 28: 11 observations
##   mean=4.545455, MSE=0.9752066 
## 
## Node number 29: 618 observations
##   mean=6.202265, MSE=0.6306098
rpart.plot(m.rpart, digits=3)

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

Q3- What is your interpretation about this amount of RMSE?

The root-mean-square error is 0.537, the lower RMSE value, the more model fit the observed data, and 0.537 is still not great.

Method 4. News Popularity

Step 1: Collecting the Data

news <- read.csv("C:/Users/zeemo/Desktop/Files/Data/RStudio/OnlineNewsPopularity_for_R.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")
str(newsShort)
## 'data.frame':    39644 obs. of  17 variables:
##  $ 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 ...
##  $ num_hrefs                   : num  4 3 3 9 19 2 21 20 2 4 ...
##  $ 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 ...
##  $ kw_max_max                  : num  0 0 0 0 0 0 0 0 0 0 ...
##  $ global_sentiment_polarity   : num  0.0926 0.1489 0.3233 0.1007 0.281 ...
##  $ avg_positive_polarity       : num  0.379 0.287 0.496 0.386 0.411 ...
##  $ 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 ...

Step 2: Pre-processing

newsShort$popular = rep('na', nrow(newsShort))
for(i in 1:39644) {
     if(newsShort$shares[i] >= 1400) {
         newsShort$popular[i] = "1"} 
     else {newsShort$popular[i] = "0"}
}
newsShort$shares = newsShort$popular
newsShort$shares <- as.factor(newsShort$shares)
set.seed(12345)

news_rand <- newsShort[order(runif(10000)), ]
#Split the data into training and test datasets
news_train <- news_rand[1:9000, ]
news_test <- news_rand[9001:10000, ]

prop.table(table(news_train$shares))
## 
##         0         1 
## 0.4308889 0.5691111
prop.table(table(news_test$shares))
## 
##     0     1 
## 0.414 0.586

Step 3: Modeling and evaluation

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 Sep 06 17:32:39 2020
## -------------------------------
## 
## Class specified by attribute `outcome'
## 
## Read 9000 cases (18 attributes) from undefined.data
## 
## Decision tree:
## 
## popular = 0: 0 (3878)
## popular = 1: 1 (5122)
## 
## 
## Evaluation on training data (9000 cases):
## 
##      Decision Tree   
##    ----------------  
##    Size      Errors  
## 
##       2    0( 0.0%)   <<
## 
## 
##     (a)   (b)    <-classified as
##    ----  ----
##    3878          (a): class 0
##          5122    (b): class 1
## 
## 
##  Attribute usage:
## 
##  100.00% popular
## 
## 
## Time: 0.1 secs
news_pred <- predict(news_model, news_test)
(p <- table(news_pred, news_test$shares))
##          
## news_pred   0   1
##         0 414   0
##         1   0 586
(Accuracy <- sum(diag(p))/sum(p)*100)
## [1] 100

Q4-Try decision tree and random forest and evaluate the model

Step 1: RANDOM FOREST

news <- read.csv("C:/Users/zeemo/Desktop/Files/Data/RStudio/OnlineNewsPopularity_for_R.csv")
news <- news[,-(1:2)]

Check for outliers

news=news[!news$n_unique_tokens==701,]

minify instances

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")

Standardize the dataset

for(i in ncol(news)-1){ 
  news[,i]<-scale(news[,i], center = TRUE, scale = TRUE)
}

Model training

cred_pridRF <- predict(random_modelNews, news_test)
(p2 <- table(cred_pridRF, news_test$shares))
##            
## cred_pridRF     0     1
##           0 10531  7712
##           1  7542  9894
(Accuracy <- sum(diag(p2))/sum(p2)*100)
## [1] 57.24656
importance(random_modelNews)
##                              MeanDecreaseGini
## n_tokens_title                      111.06636
## n_tokens_content                    165.82171
## n_unique_tokens                     184.11362
## n_non_stop_words                    167.86920
## num_hrefs                           131.42586
## num_imgs                             99.78308
## num_videos                           56.95850
## average_token_length                197.00327
## num_keywords                         96.41648
## kw_max_max                           54.20264
## global_sentiment_polarity           209.21613
## avg_positive_polarity               190.79576
## title_subjectivity                   77.55101
## title_sentiment_polarity             85.25876
## abs_title_subjectivity               70.34923
## abs_title_sentiment_polarity         70.29701

Step 2: Decision Tree

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 Sep 06 17:32:46 2020
## -------------------------------
## 
## Class specified by attribute `outcome'
## 
## Read 3964 cases (17 attributes) from undefined.data
## 
## Decision tree:
## 
## num_imgs > 3:
## :...n_tokens_title <= 9:
## :   :...num_imgs <= 14:
## :   :   :...avg_positive_polarity > 0.4936364: 1 (20)
## :   :   :   avg_positive_polarity <= 0.4936364:
## :   :   :   :...title_sentiment_polarity <= -0.375: 0 (13/4)
## :   :   :       title_sentiment_polarity > -0.375: 1 (207/59)
## :   :   num_imgs > 14:
## :   :   :...kw_max_max <= 690400: 0 (26/7)
## :   :       kw_max_max > 690400:
## :   :       :...num_keywords <= 4: 0 (7/1)
## :   :           num_keywords > 4: 1 (88/30)
## :   n_tokens_title > 9:
## :   :...n_tokens_title > 14: 0 (32/11)
## :       n_tokens_title <= 14:
## :       :...n_tokens_content <= 452: 1 (256/85)
## :           n_tokens_content > 452:
## :           :...kw_max_max <= 617900:
## :               :...num_hrefs <= 6: 1 (11/2)
## :               :   num_hrefs > 6: 0 (34/8)
## :               kw_max_max > 617900:
## :               :...num_keywords <= 6: 0 (103/42)
## :                   num_keywords > 6: 1 (278/123)
## num_imgs <= 3:
## :...global_sentiment_polarity > 0.09618686:
##     :...kw_max_max > 73100:
##     :   :...n_tokens_content <= 859:
##     :   :   :...num_imgs <= 1: 0 (1125/525)
##     :   :   :   num_imgs > 1: 1 (152/66)
##     :   :   n_tokens_content > 859:
##     :   :   :...num_hrefs <= 4: 0 (13/2)
##     :   :       num_hrefs > 4: 1 (216/75)
##     :   kw_max_max <= 73100:
##     :   :...abs_title_subjectivity <= 0.02272727: 1 (17)
##     :       abs_title_subjectivity > 0.02272727:
##     :       :...num_hrefs <= 4: 1 (36/8)
##     :           num_hrefs > 4:
##     :           :...title_subjectivity > 0.75: 1 (11)
##     :               title_subjectivity <= 0.75:
##     :               :...n_tokens_content <= 1020: 0 (73/28)
##     :                   n_tokens_content > 1020: 1 (7)
##     global_sentiment_polarity <= 0.09618686:
##     :...average_token_length > 4.633452:
##         :...n_tokens_title > 8: 0 (609/179)
##         :   n_tokens_title <= 8:
##         :   :...n_unique_tokens > 0.5629771:
##         :       :...avg_positive_polarity <= 0.1463265: 1 (4)
##         :       :   avg_positive_polarity > 0.1463265: 0 (56/13)
##         :       n_unique_tokens <= 0.5629771:
##         :       :...abs_title_subjectivity <= 0.1388889: 1 (7)
##         :           abs_title_subjectivity > 0.1388889:
##         :           :...n_tokens_title <= 7: 1 (15/3)
##         :               n_tokens_title > 7: 0 (35/15)
##         average_token_length <= 4.633452:
##         :...kw_max_max <= 690400: 1 (114/40)
##             kw_max_max > 690400:
##             :...num_keywords <= 6: 0 (191/62)
##                 num_keywords > 6:
##                 :...n_non_stop_words <= 0: 1 (57/23)
##                     n_non_stop_words > 0:
##                     :...num_hrefs > 3: 1 (122/53)
##                         num_hrefs <= 3:
##                         :...n_tokens_title > 10: 0 (20/2)
##                             n_tokens_title <= 10:
##                             :...title_sentiment_polarity <= -0.05: 0 (4)
##                                 title_sentiment_polarity > -0.05: 1 (5)
## 
## 
## Evaluation on training data (3964 cases):
## 
##      Decision Tree   
##    ----------------  
##    Size      Errors  
## 
##      34 1466(37.0%)   <<
## 
## 
##     (a)   (b)    <-classified as
##    ----  ----
##    1442   567    (a): class 0
##     899  1056    (b): class 1
## 
## 
##  Attribute usage:
## 
##  100.00% num_imgs
##   72.88% global_sentiment_polarity
##   68.37% kw_max_max
##   57.21% n_tokens_content
##   46.17% n_tokens_title
##   31.26% average_token_length
##   22.07% num_keywords
##   13.93% num_hrefs
##    7.57% avg_positive_polarity
##    5.78% title_sentiment_polarity
##    5.25% n_non_stop_words
##    5.07% abs_title_subjectivity
##    2.95% n_unique_tokens
##    2.30% title_subjectivity
## 
## 
## Time: 0.1 secs

Model training

news_pred <- predict(news_model, news_test)
CrossTable(news_test$shares, news_pred, prop.chisq = FALSE, prop.c = FALSE, prop.r = FALSE, dnn = c('actual shares', 'predicted shares'))
## 
##  
##    Cell Contents
## |-------------------------|
## |                       N |
## |         N / Table Total |
## |-------------------------|
## 
##  
## Total Observations in Table:  35679 
## 
##  
##               | predicted shares 
## actual shares |         0 |         1 | Row Total | 
## --------------|-----------|-----------|-----------|
##             0 |     11669 |      6404 |     18073 | 
##               |     0.327 |     0.179 |           | 
## --------------|-----------|-----------|-----------|
##             1 |      9231 |      8375 |     17606 | 
##               |     0.259 |     0.235 |           | 
## --------------|-----------|-----------|-----------|
##  Column Total |     20900 |     14779 |     35679 | 
## --------------|-----------|-----------|-----------|
## 
## 
(p3 <- table(news_pred, news_test$shares))
##          
## news_pred     0     1
##         0 11669  9231
##         1  6404  8375
(Accuracy <- sum(diag(p3))/sum(p3)*100)
## [1] 56.1787