Twitter metnini işleme

R ile Sosyal Medya Verilerini Analiz Etme

Vivek Vijayaraghavan

Data Science Coach

Ders özeti

Neden tweet metni işlenir?
Tweet metni işleme adımları
- gereksiz bilgiyi kaldırma
- Metni bir derlemeye dönüştürme
- Durak sözcükleri kaldırma

Neden tweet metnini işleriz?

Tweet metni yapılandırılmamış, gürültülü ve hamdır
İfadeler, URL’ler, sayılar içerir
Analiz ve güvenilir sonuçlar için temizlik gerekir

Metin işlemedeki adımlar

Adım1: Gereksiz bilgiyi kaldırma

Metin işlemedeki adımlar

Adım2: Metni derlemeye dönüştürme

Metin işlemedeki adımlar

Adım3: Küçük harfe dönüştürme

Metin işlemedeki adımlar

Adım4: Durak sözcükleri kaldırma

Tweet metnini çıkarma

# Extract 1000 tweets on "Obesity" in English and exclude retweets
tweets_df <- search_tweets("Obesity", n = 1000, include_rts = F, lang = 'en')

# Extract the tweet texts and save it in a data frame
twt_txt <- tweets_df$text

Tweet metnini çıkarma

head(twt_txt, 3)

[1] "@WeeaUwU for real, obesity should not be praised like it is in today's society" 

[2] "Great work by @DosingMatters in @AJHPOfficial on \"Vancomycin Vd estimation in 
adults with class III obesity\". As we continue to study/learn more about dosing in 
large body weight pts, we see that it's not a simple, one size, one level estimate 
that works https://t.co/KkYPqS6JzG" 

[3] "The Scottish Government have an ambition to halve childhood obesity by 2030. 
This means reducing obesity prevalence in 2-15yo children in Scotland to 7%. 
\n\n\U0001f449 In 2018, this figure was 16%\n\nFind out more in our latest blog: 
https://t.co/FWp56QWjQc https://t.co/XBK8Je7F1A"

URL'leri kaldırma

# Remove URLs from the tweet text
library(qdapRegex)
twt_txt_url <- rm_twitter_url(twt_txt)

URL'leri kaldırma

twt_txt_url[1:3]

[1] "@WeeaUwU for real, obesity should not be praised like it is in today's society"

[2] "Great work by @DosingMatters in @AJHPOfficial on \"Vancomycin Vd estimation in  adults 
with class III obesity\". As we continue to study/learn more about dosing in large body 
weight pts, we see that it's not a simple, one size, one level estimate that works"

[3] "The Scottish Government have an ambition to halve childhood obesity by 2030. 
This means reducing obesity prevalence in 2-15yo children in Scotland to 7%. 
\U0001f449In 2018, this figure was 16% Find out more in our latest blog:"

Özel karakterler, noktalama ve sayılar

# Remove special characters, punctuation & numbers
twt_txt_chrs  <- gsub("[^A-Za-z]", " ", twt_txt_url)

Özel karakterler, noktalama ve sayılar

twt_txt_chrs[1:3]

[1] " WeeaUwU for real  obesity should not be praised like it is in today s society"

[2] "Great work by  DosingMatters in  AJHPOfficial on  Vancomycin Vd estimation in 
adults with class III obesity   As we continue to study learn more about dosing in 
large body weight pts  we see that it s not a simple  one size  one level estimate 
that works"

[3] "The Scottish Government have an ambition to halve childhood obesity by       This 
means reducing obesity prevalence in     yo children in Scotland to       In       this 
figure was     Find out more in our latest blog "

Metni derlemeye dönüştürme

# Convert to text corpus
library(tm)
twt_corpus <- twt_txt_chrs %>% 
                VectorSource() %>% 
                Corpus()

twt_corpus[[3]]$content

[1] "The Scottish Government have an ambition to halve childhood obesity by       
This means reducing obesity prevalence in     yo children in Scotland to       In  
     this figure was     Find out more in our latest blog "

Küçük harfe dönüştürme

Büyük/küçük harf farkı, aynı sözcüğü iki farklı sözcük gibi saymamalıdır

# Convert text corpus to lowercase
twt_corpus_lwr <- tm_map(twt_corpus, tolower) 
twt_corpus_lwr[[3]]$content

[1] "the scottish government have an ambition to halve childhood obesity by     this 
means reducing obesity prevalence in     yo children in scotland to       in    this 
figure was     find out more in our latest blog "

Durak sözcük nedir?

Durak sözcükler, a, an, and, but gibi sık kullanılan sözcüklerdir

# Common stop words in English
stopwords("english")

İngilizcedeki varsayılan durak sözcükler

Durak sözcükleri kaldırma

Önemli sözcüklere odaklanmak için durak sözcükler kaldırılmalıdır

# Remove stop words from corpus
twt_corpus_stpwd <- tm_map(twt_corpus_lwr, removeWords, stopwords("english"))

twt_corpus_stpwd[[3]]$content

[1] " scottish government   ambition  halve childhood obesity         means 
reducing obesity prevalence      yo children  scotland                figure      
find     latest blog "

Ek boşlukları kaldırma

Temiz bir derlem için ek boşlukları kaldırın

# Remove additional spaces
twt_corpus_final <- tm_map(twt_corpus_stpwd, stripWhitespace)

twt_corpus_final[[3]]$content

[1] " scottish government ambition halve childhood obesity means reducing obesity 
prevalence yo children scotland figure find latest blog "

Haydi pratik yapalım!

R ile Sosyal Medya Verilerini Analiz Etme