rm(list=ls())

#BEL2    !
#These days, I feel like I belong.    
#   (values 1 thru 7) 1: not true, 7: very true
#BSS8     (values: 0, 1, 2) (rare, frequent, continuous)
#   I accept the idea of killing myself.
#IBS3    O
#Have you had any self-mutilation thoughts and impulses 
#    (without taking action)? 
#IBS15   H
#Have you had any suicidal thoughts and impulses (without taking action)?

# Question
#1.	Is level of belongingness related to level of suicidal ideation?
# Answer
# I will use correlation to establish any relation

# We will use tools from categories

#----------------------------------------------------------------------
# all numerical data, but this data links to textual answers
file = "VanOrden_for dist.csv"
dall = read.csv(file)
dall
#d = dall[c("bel2","bss8")]
d = dall[c("bel2","ibs15")]
d

# clean up unused variables
rm(dall)

# bss8 has many 999 undefines. Must get rid of them
d = d[d$ibs15 != 999,]
#d = d[d$bel2 != 999,]
d

t = table(d)
total = sum(t)
rowsum = apply(t,1,sum)
colsum = apply(t,2,sum)
prop = t/total
rowprop = sweep(t,1,rowsum,"/")
colprop = sweep(t,2,colsum,"/")

l = list(s.table=t,
         s.total=total,
		 s.rowsum=rowsum,
		 s.colsum=colsum,
		 s.prop=prop,
		 s.colprop=colprop,
		 s.rowprop=rowprop)

print("-----------------")
l$s.total
print("-----------------")
l$s.table
l$s.rowsum
l$s.colsum
l$s.rowprop
l$s.colprop
print("-----------------")

# Chi-Square testing

chisq.test(l$s.table)

### Cannot do this. WHY NOT?
### chisq.test(l$s.prop)
### The reason is likely that there are not enough samples. 

y = l$s.table[1:4,2:3]
y
#y
print("*** chisq.test(y) ***")
chisq.test(y)

#prop.test(y,y)

print("================")
chisq.test(y,y)
print("================")