Question

  You are studying the relationship between smoking and hair loss. You find a positive moderate effect size. You conclude:

	A.	there is clinical significance
	B.	the correlation between smoking and hair loss is between -0.3 and -0.5
	C.	the correlation between smoking and hair loss is between 0.3 and 0.5
	D.	this is a significant relationship

Answer 1

We can measure the strength of relationship between two variable by calculatin the coefficient of correlation.

Value of r lies between -1 to 1,

Indicate - If value of r is in negative, it means negative relation between the variables

for example say X and Y are two variables, if r is negative it means that rise in value of X by 1 unit makes fall in Y by 1 unit.

Similarly, if r is positive the we say that rise in value of X by 1 unit, makes rise in Y by 1 unit

r = -1 OR 1 indicate strong relationship between variables

and if r near to 0 indicate week relationship between the variables

In the question it is mention that relationship is positive and moderate

Positive relationship :- Coefficient of correlation takes positive value

Moderate :- It indicate correlation coefficient lies between 0.2 to 0.6

Looking at the options we can see that option C statisfies the condition

Since Coefficient of Correlation is between 0.3 to 0.5, it do incdicate that r takes positive value as well as the relationship is moderate ( r lies between 0.2 to 0.6 )

Option C is correct.