Assignment 1

About Me

My name is Syd Del Colombo, I am a second year student doing a major in mathematics. In my spare time when I am not at school I enjoy doing art and hanging out with my friends. I love to going out, explore and party all around the world

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Me (on the right) enjoying a drink on a rooftop bar in Madrid.

anorexia<-na.omit(read.csv("anorexia.csv"))
str(anorexia)

'data.frame':   72 obs. of  4 variables:
 $ subj   : int  1 2 3 4 5 6 7 8 9 10 ...
 $ therapy: chr  "b" "b" "b" "b" ...
 $ before : num  80.5 84.9 81.5 82.6 79.9 88.7 94.9 76.3 81 80.5 ...
 $ after  : num  82.2 85.6 81.4 81.9 76.4 ...

anorexia$therapy<-factor(anorexia$therapy)
str(anorexia)

'data.frame':   72 obs. of  4 variables:
 $ subj   : int  1 2 3 4 5 6 7 8 9 10 ...
 $ therapy: Factor w/ 3 levels "b","c","f": 1 1 1 1 1 1 1 1 1 1 ...
 $ before : num  80.5 84.9 81.5 82.6 79.9 88.7 94.9 76.3 81 80.5 ...
 $ after  : num  82.2 85.6 81.4 81.9 76.4 ...

Data Description

https://users.stat.ufl.edu/~aa/social/csv_files/anorexia.csv 

• Subject contains the number of subjects in the data set

• Therapy contains the type of therapy each participant received

  • b = cognitive behavioral

  • c = control

  • f = family treatment

• Before is the weight (lbs) of participants before treatment

• After is the weight (lbs) of participants after treatment
  

\[ P(E)={n\choose k}p^k(2-p)^{n-k} \]

beforemean<-mean(anorexia$before)
aftermean<-mean(anorexia$after)
beforemean

[1] 82.40833

aftermean

[1] 85.17222

freq_table<-table(anorexia$therapy)
print(freq_table)

 b  c  f 
29 26 17 

---

---

barplot(freq_table, col="lightblue",
                  main="Girls in Therapy")

before<-anorexia$before
hist(before, main="Anorexia")

before<-anorexia$before
after<-anorexia$after
plot(x=before, y=after,main="Anorexia", col=anorexia$therapy,
     xlab="Before(lbs)",ylab="After(lbs)"
     )
legend("topright",legend = c("cognitive behavioural","family therapy","control"),fill=1:10,border="black") 

boxplot(anorexia$before, anorexia$after,names=c("before","after"))

median(anorexia$before)

[1] 82.3

median(anorexia$after)

[1] 84.05

IQR(anorexia$before)

[1] 6.4

IQR(anorexia$after)

[1] 12.225

sd(anorexia$before)

[1] 5.182466

sd(anorexia$after)

[1] 8.035173

• median: for before seems to be about 82 and for after it seems to be 85\

  • actual: median before = 82.3, median after = 84.05

• IQR: for before is about 5 and for after would be 12

  • actual: before=6.4, after=12.2

Standard deviation: I think “after” will have a higher standard deviation

Before=5.18, After= 8.04

There could be an outliar in the “after” portion of the max whisker is a lot higher than the “before” whisker.