a=5
a
## [1] 5
ls()
## [1] "a"
load('C:/Users/Marta/Desktop/tirpitz/R/fratings3000.RData')
summary(mratings)
##      USERID           MOVIEID          RATING            TS            
##  Min.   :    195   Min.   :    1   Min.   :1.000   Min.   :1999-12-30  
##  1st Qu.: 663373   1st Qu.: 4686   1st Qu.:3.000   1st Qu.:2004-07-05  
##  Median :1347602   Median : 9189   Median :4.000   Median :2005-02-18  
##  Mean   :1331206   Mean   : 9135   Mean   :3.633   Mean   :2004-11-22  
##  3rd Qu.:2000221   3rd Qu.:13748   3rd Qu.:4.000   3rd Qu.:2005-07-25  
##  Max.   :2648758   Max.   :17770   Max.   :5.000   Max.   :2005-12-31  
##                                                                        
##        K              MAVG            CNT            BAYESAVG    
##  Min.   :  1.0   Min.   :1.000   Min.   :   1.0   Min.   :2.820  
##  1st Qu.: 42.0   1st Qu.:3.389   1st Qu.: 105.0   1st Qu.:3.472  
##  Median :105.0   Median :3.640   Median : 306.0   Median :3.637  
##  Mean   :142.7   Mean   :3.632   Mean   : 392.7   Mean   :3.657  
##  3rd Qu.:212.0   3rd Qu.:3.890   3rd Qu.: 630.0   3rd Qu.:3.833  
##  Max.   :598.0   Max.   :5.000   Max.   :1398.0   Max.   :4.532  
##                  NA's   :118     NA's   :118      NA's   :118    
##       TT              IMDBRATING       GENRE1              YEAR          
##  Length:471074      Min.   :1.90    Length:471074      Length:471074     
##  Class :character   1st Qu.:6.40    Class :character   Class :character  
##  Mode  :character   Median :7.00    Mode  :character   Mode  :character  
##                     Mean   :6.95                                         
##                     3rd Qu.:7.60                                         
##                     Max.   :9.20                                         
##                     NA's   :60932                                        
##      USHIFT            USHIFTB            UGENRE          GENREMATCH     
##  Min.   :-2.02088   Min.   :-1.10638   Length:471074      Mode :logical  
##  1st Qu.:-0.30507   1st Qu.:-0.23972   Class :array       FALSE:258414   
##  Median :-0.03721   Median :-0.02774   Mode  :character   TRUE :149315   
##  Mean   :-0.02477   Mean   :-0.02363                      NA's :63345    
##  3rd Qu.: 0.23167   3rd Qu.: 0.17260                                     
##  Max.   : 1.43803   Max.   : 1.06262                                     
## 
attach(mratings)
#min(mratings$USERID)
median(RATING)
## [1] 4
hist(RATING)

hist(IMDBRATING,main='FLIX - IMDBRATING')

plot(CNT,MAVG)

cor.test(RATING,MAVG,method='pearson')
## 
##  Pearson's product-moment correlation
## 
## data:  RATING and MAVG
## t = 277.26, df = 470950, p-value < 2.2e-16
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  0.3721412 0.3770517
## sample estimates:
##       cor 
## 0.3745991
cor.test(RATING, IMDBRATING)
## 
##  Pearson's product-moment correlation
## 
## data:  RATING and IMDBRATING
## t = 173, df = 410140, p-value < 2.2e-16
## alternative hypothesis: true correlation is not equal to 0
## 95 percent confidence interval:
##  0.2579317 0.2636362
## sample estimates:
##       cor 
## 0.2607862
boxplot(IMDBRATING~RATING,data=mratings,xlab='RATING',ylab='IMDBRATING')

boxplot(MAVG~RATING,data=mratings,xlab='RATING',ylab='MAVG',main="MAVG vs. RATING")
linModel=lm(MAVG~RATING, data=mratings)
abline(linModel$coefficients, col='blue')
mtext(linModel$coefficients[2],1,col='blue')

boxplot(RATING~GENRE1,data=mratings,ylab='RATING',xlab='', main='RATING vs. GENRE', las=2,text.cex=0.5)

par(mfrow=c(2,3))
for(i in 1:5)hist(mratings[RATING==i,'IMDBRATING'],xlab='IMDBRATING',main=paste0('RATING==',i))

imdb_range=sort(unique(IMDBRATING))
rating_range=sort(unique(RATING))
tab_rat=table(IMDBRATING,RATING)
#table(IMDBRATING)
#mratings[RATING==4 & IMDBRATING]
#contour(imdb_range,rating_range,tab_rat,nlevels=45,add=T)
#image(imdb_range,rating_range,tab_rat)
persp(imdb_range,rating_range,tab_rat,theta=40,phi=20)

ucounts=tapply(RATING,USERID,FUN=length)
hist(ucounts,main="# Rated Movies per User",xlab='#ratings',ylab='#users with the #ratings')