Page 1 of 1

Cross-Correlation

Posted: Sun May 03, 2009 10:57 am
by K.I.S.S
I am running two different variables in EViews using the Cross-Correlogram function and i want to know how this function can tell that independent variable is a leading indicator of the dependent variable. If anyone knows how to read or translate the results from a cross-correlogram i would greatly appreciate the help.

Re: Cross-Correlation

Posted: Mon May 04, 2009 12:20 am
by trubador
By default, cross correlation displays correlograms from 0 to 36 leads-lags for a pair of series (say y and z). If, for example, z is a leading indicator of y, then you should observe the highest significant correlation at a lag greater than 0. In other words, correlation between y and z(-i) or y(+i) and z, where i>0, should be higher compared to other lags (leads). The reading changes with respect to ordering of variables.

Re: Cross-Correlation

Posted: Mon Sep 14, 2009 6:51 am
by Ruslan
Sorry, have the same question, and it is still not clear.

Let's say it in this way:
Grouping Y and Z, then, open cross-correlation at 5 lag.

Lets say we have the following result:
Date: 14/09/09 Time: 14:40
Sample: 2/01/1996 31/12/2007
Included observations: 3130
Correlations are asymptotically consistent approximations

Y,Z(-i) Y,Z(+i) i lag lead

|* | |* | 0 0.0948 0.0948
| | |*** |1 -0.0359 0.3185
| | |* | 2 -0.0069 0.0560
| | | | 3 0.0207 -0.0019
| | | | 4 -0.0204 0.0130
| | | | 5 -0.0105 0.0045

The question is: In Y,Z(-I) we observe the correlation at a given lags in the assumption where Y led by Z?
Or in Y,Z(-I) we have the assumption that Y lead Z?

file attached:
ccf_look.wf1
(84.2 KiB) Downloaded 1525 times
Thank you.

Re: Cross-Correlation

Posted: Mon Sep 14, 2009 7:09 am
by trubador
Variable Y should be considered as the leading indicator of variable Z, since the highest correlation occurs at the first lead. In other words, you'll get the most explanatory power if you regress variable Z on the first lag of variable Y:

Code: Select all

equation eq1.ls z c y(-1)
or if you regress the first lead of variable Z on variable Y:

Code: Select all

equation eq1.ls z(1) c y

Re: Cross-Correlation

Posted: Mon Sep 14, 2009 7:22 am
by Ruslan
so, If I understand you correctly, column Y,Z(+i) refers to Y leads Z assumption.
And the highest correlation at the first lead is confirmation of causality at lag 1 from Y to Z.

Is it correct?

Thank you.

Your regression adding makes it clear.

But I think, headings in cross-correlation output is not clear. Also, user guide on this question is poor (just formulas, no explanation).

Thank you.

Best wishes,
Ruslan.

Re: Cross-Correlation

Posted: Mon Sep 14, 2009 7:36 am
by trubador
Yes, that is correct. However, please keep in mind that this analysis does not confirm the causality but rather determines the time lag between two variables.