Hi Colin,
Kriging, in it's native state, does not
ensure positivity of the weights or the estimates. The methodology does not
'know' that such and such a variable (eg concentrations in ppm or permeability
in md) has to be positive. For the most part this is a good thing. Consider the
'pic
Colin
> Is my understanding of this "compensation" correct?
Exactly.
> Why wouldn't the weights for the furtherest samples
> be calculated by subtracting the weighting of the
> closer samples from 1, instead of compensating using
> negative weights afterwards?
I am not sure I understand your que
I have recently carried out ordinary kriging for a
ore reserve estimation exercise (using GSLIB), and noted that a very few of
the grade estimates are negative (always a very small number e.g. 0.002
ppm). I have been able to trace this back to negative kriging weights, and would
like some co
According to Noel Cressie's book (Statistics for
spatial dat, Wiley, p427)
"Moran (1948) proposed a test of spatial dependence
between sites...
The statistic I is known as Moran's contiguity ratio;
it tests for random spatial scatter of, say, black
sites in black/white images ..."
Hello AI-Geostats members
I set this mail to AI-GEOSTATS , But I did not recieve any response, therefore I send
it again:
I saw Marrons I Statistic in GS+ Software. It is an statistic computed in
each lags as follow:
N(h){sum(Zi*Zj)/sum(Zi^2)}
This statistics and its plot arise for me
Dear All,
I had a couple of questions regarding the calculation and use of Moran's I.
Firstly, does anyone know of free software or routines that will calculate
Moran's I (for user defined lags) and provide a significance value for the
calculated statistic? I have played with Crimestat (thank
Dear All,
A sincere apology that it has taken be so long to post the responses to a
query I sent earlier this year.
The content of my posting and the replies I received are listed below.
Thank you once again to those that responded, your input has been extremely
helpful.
Raechel Waters
Orig
Hi,
> I have the 3.1 version of GS+ and everything is going ok, but when I
>ask for the program to make the color maps i get these
> crazy
>squares and nothing related to what I want. Also the
> example data that
>comes with the program also gives these crazy
