[gradsusr] P-value of scorr & tcorr

[James Ciarlo`]

Hi Teresa,

I have found this, maybe it will be helpful

http://ccr.aos.wisc.edu/climate_modeling/modeling/data_processing/grads/grads_statsig.php

Regards,

James

On 22 July 2011 16:36, James Ciarlo` <james.ciarlo at physics.org> wrote:

> Hi Teresa,
>
> sorry for replying so late, i had some personal issues. well I have some
> difficulties with this technique since I have statistically significant
> values both negative and positive, so when i do set cmin or cmax, it will
> block out the others. Is there a way to set it to absolute values?
>
> With regards to scorr, I am of the understanding that grads correlates the
> final spatial distribution of both and thus producing one value. I guess for
> statistical significance one can use the values on statistics books, and
> also consider the resolution of the image to obtain n
>
> Regards,
>
> James
>
>
> On 20 May 2011 17:41, <tcavazos at cicese.mx> wrote:
>
>> Hi,
>>
>> A simple way for tcorr: look at the statistically significant values for
>> correlation in a statistics book; then according to your n-1 observations
>> get the threshold values for the level of interest (p<0.05 or p<0.01).
>>
>> In grads you you can black out the values lower than those thresholds to
>> display only the significant ones. Also you can set a minimum value to
>> plot. For example, if your significant correlation at the 95% level is
>> 0.45:
>>
>> "set cmin 0.45"
>>
>> By the way how do you calculate the scorr, do you only average the spatial
>> window after calculating the tcorr?
>>
>> The spatial significance is much more complicated...I am also interested
>> in that, if anyone has it. It may require a bootstrap...
>>
>> Tereza Cavazos
>>
>>
>> > Dear gradsusrs,
>> >
>> > I have a question about scorr and tcorr functions. Is there a way to
>> > obtain
>> > the p-value in this cases? i.e. one value for scorr and map value for
>> > tcorr
>> >
>> > Or anything of the sort?
>> >
>> > Regards,
>> >
>> > James
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>>
>>
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