Map > Problem Definition > Data Preparation > Data Exploration > Bivariate
 

Data Exploration - Bivariate Analysis

I. Data Preparation

1- Load libraries

library(data.table)
library(formattable)
library(plotrix)
library(limma)
 

2- Read Expressions file

df <- read.csv("GSE74763_rawlog_expr.csv")
df2 <- df[,-1]
rownames(df2) <- df[,1]
expr <- transpose(df2)
rownames(expr) <- colnames(df2)
colnames(expr) <- rownames(df2)
dim(expr)
 

3- Read Samples file

targets <- read.csv("GSE74763_rawlog_targets.csv")
colnames(targets)
dim(targets)
 

4- Merge Expressions with Samples

data <- cbind(expr, targets)
colnames(data)
dim(data)
 
II. Numerical & Numerical
1- Linear Correlation
cor(data$P000001,data$P000002)

 
2- Scatter plot
pairs(~P000001+P000002, data=data, main="GSE74763_rawlog", col="darkgreen")

 
III. Categorical & Categorical
1- Count (crosstab)
xtabs(~target+gender, data=data)

 
2- CrossTab Plot
xt <- xtabs(~target+gender, data=data)
plot(xt, main="GSE74763_rawlog", col="darkgreen")

3- Chi2 test
tbl <- table(data$target, data$gender)
chisq.test(tbl)

 
IV. Categorical & Numerical
1- Box plot
boxplot(P000001~target, data=data, col="darkgreen", main="GSE74763_rawlog", ylab="P000001 - intensity")

 
2- t-test
t.test(data$P000002~data$target)

 
3- ANOVA
fit <- aov(P000001~target, data=data)
summary(fit)

 
V. Bioada SmartArray
Watch this video to learn how you can perform bivariate analysis using Bioada SmartArray significantly faster and easier.