Linear Correlation and Modeling

Key Questions

  • What is the range of possible values of a correlation coefficient?

    The possible values of the correlation coefficient are, -1<=r<=1.

    An r value near 1 indicates a positive correlation.
    An r value near -1 indicates a negative correlation.
    An r value near 0 indicates no correlation.

    AJ Speller · 6 · Sep 14 2014
  • How do I find and interpret the linear correlation coefficient?

    Answer:

    See explanation. I would suggest that you look it up in a book. Dictionary of mathematics perhaps.

    Explanation:

    color(blue)("Finding the coefficient")

    This is one of those questions that is rather like: "how long is a piece of string".

    It all depends on the structure of the relationship which has many variations. So it is hard to give a definitive answer.

    Linea points to a fixed value coefficient.

    By example:

    Let the independent variable be x
    Let the dependant variable be y
    Let the correlation coefficient be k

    Then we have the general form of;

    y=kx

    To find the value of k divide both sides by x giving:

    k=y/x
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    color(blue)("Interpreting the coefficient")

    Again this is dependant on context. Basically it fixes the major relationship between the dependant and independent variables.

    It could be described as a conversion factor

    Tony B · 1 · Jan 2 2017

Questions

Linear and Quadratic Functions