Dear members

I am presently working with rainfall and groundwater level data. Using SPSS (v
13), I did auto-correlation and cross-correlation for water level and rainfall
data.

I like to clarify the output of this analysis.

Data details

Water level – Monthly data from 1984 to 2003
Rainfall - Monthly data from 1984 to 2003.

1) I got an output with a warning “ Some of the missing cases are imbedded
within the series”. I think it may be due to missing values in the water level
data series.

Will it affect the result?

CROSS-CORRELATION

2) In SPSS, I had selected the rainfall as a first variable (for Input) and
water level as a second variable (for Output). I like to give the rainfall data
as input and water level data as output.

Is it right?

3) In the Cross-correlation curve, highest correlation value (CCF , Max) is
observed with negative lag.

How to explain this?

4) In some wells, highest correlation value is not observed as a single point
(one lag) in cross-correlation curve, but it is observed in multiple point
(multiple lag. Eg. 0.2 is observed at 10 lag, 22 lag, etc.).

5) Also, the cross-correlation value (CCF) is less than 0.2. Is it
acceptable?

Can anyone help me to solve this problem?

Thanks in advance

Yours sincerely
Rajmohan






__________________________________________________
Do You Yahoo!?
Tired of spam? Yahoo! Mail has the best spam protection around
http://mail.yahoo.com

[Non-text portions of this message have been removed]