Manuals/calci/CORREL

From ZCubes Wiki
Revision as of 22:58, 9 December 2013 by Abin (talk | contribs) (→‎Description)
Jump to navigation Jump to search
CORREL(ar1,ar2)


  • Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle ar1} and Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle ar2 } are the set of values.

Description

  • This function gives the correlation coefficient of the 1st set(Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle ar1} ) of values and 2nd set(Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle ar2} ) of values.
  • Correlation is a statistical technique which shows the relation of strongly paired variables.
  • For example, test average and study time are related; those who spending more time to study will get high marks and Average will go down for those who spend less time for studies.
  • There are different correlation techniques to measure the Degree of Correlation.
  • The most common of these is the Pearson Correlation Coefficient denoted by r xy.
  • The main result of a correlation is called the Correlation Coefficient(Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle r} )which ranges from -1 to +1.
  • The Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle r} value is positive i.e +1 when the two set values increase together then it is the perfect Positive Correlation.
  • The Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle r} value is negative i.e. (-1) when one value decreases as the other increases then it is called Negative Correlation.
  • Suppose the Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle r} value is 0 then there is no correlation (the values don't seem linked at all).
  • If we have a series of Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle n} measurements of Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle X} and Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle Y} written as Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle xi} and Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle yi} where Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle i} = 1, 2,...n then the Sample Correlation Coefficient is:
Failed to parse (syntax error): {\displaystyle CORREL(X,Y)= r_{xy}=\frac{\sum_{i=1}^n(xi-\bar x)(yi-\bar y)}{\sqrt{ \sum_{i=1}^n (xi-\bar x)^2 \sum{i=1}^n(yi-\bar y)^2}}
, where x(bar) and y(bar) are the sample means of X and Y. *This function will give the result as error when
  1. ar1 and ar2 are nonnumeric or different number of data points.
  2. ar1 or ar2 is empty
  3. The denominator value is zero.
  • Suppose ar1 and ar2 contains any text, logical values, or empty cells, like that values are ignored.

Examples

  1. 1. Find the correlation coefficients for X and Y values are given below :X={1,2,3,4,5}; Y={11,22,34,43,56}

CORREL(A4:A8,B4:B8)=0.99890610723867

  1. The following table gives the math scores and times taken to run 100 m for 10 friends:SCORE(X)={52,25,35,90,76,40}; TIME TAKEN(Y)={11.3,12.9,11.9,10.2,11.1,12.5}CORREL(A5:A10,B5:B10)= -0.93626409417769
  2. Find the correlation coefficients for X and Y values are given below :X={-4,11,34,87};Y={9,2,59,24} CORREL(A1:A4,B1:B4)=0.353184665607273

See Also


References

Bessel Function

Retrieved from "http://wiki.zcubes.com/index.php?title=Manuals/calci/CORREL&oldid=196262"