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Correlations for spatio-temporal data ?
2 messages · Jian Zhang, David Duffy
On Sun, 11 Dec 2011, Jian Zhang wrote:
I have a dataset like this:
sites years Var1 Var2
1 1960 505 3.013833
....
5 1960 476 4.337246
5 1961 540 8.601403
5 1962 610 18.99233
5 1963 479 1.336739
5 1964 822 43.73037
5 1965 692 30.30235
Meantime, I have the spatial location (longitude, latitude) for each
site. Among these sites, spatial autocorrelation exists. Within each
site, for the variables Var1 and Var2, temporal autocorrelation
also exists. I want to calculate the correlation between Var1 and Var2
using correlation coefficient. My question is that how can I add the
information of spatial and temporal autocorrelation into my analysis. I
know that, for only spatial autocorrelation, we can use modified
t-test to do the analysis. But I have no idea how to do it when
considering the spatial and temporal autocorrelation together?
If the data is as regular as in your example (fixed set of years for every site etc), you could fit this as a structural equation model to the summary covariance matrix using, for example, the sem package. Just 2c, David Duffy.
| David Duffy (MBBS PhD) ,-_|\ | email: davidD at qimr.edu.au ph: INT+61+7+3362-0217 fax: -0101 / * | Epidemiology Unit, Queensland Institute of Medical Research \_,-._/ | 300 Herston Rd, Brisbane, Queensland 4029, Australia GPG 4D0B994A v