Correlation diagram
Submitted by azaquar on Wed, 18/05/2011 - 11:17
Overview
The correlation diagram is also called "Chart of dispersion."
What is the correlation diagram?
The correlation diagram to illustrate the relationship between two variables and phenomena to observe the influence of one over the other.
The calculation and plot of the regression line is very useful to predict the value of Y based on X. Indeed, it allows to express in mathematical form the relationship between variables X and Y.
How to use the correlation diagram?
The use of correlation diagram goes through several phases:
- Determine the two phenomena to be studied (Cause-Effect).
- Collect pairs of data to use.
- Charting the question on the X axis and the effect on the Y axis
- Point on the graph, pairs of data.
- Find the equation of the regression line (Y = aX + b), calculate the correlation coefficient r2 and draw the regression line.
- Analyze the graph.
Example diagram correlation
The following example illustrates the relationship between the size of children and parents.
