Maxent max, min, std and average ascii outputs

[Neil Daniels]

Hi all

I ran 10 replicates using maxent. I notice there are max, min, std and average ascii  probability of occurrence maps. 

For these avg, max, min and std maps, are these the respective avg, max, min, and std values averaged over the ten replicates I ran?

Kind regards

Neil Daniels

Disclaimer - This e-mail is subject to UWC policies and e-mail disclaimer published on our website at: https://www.uwc.ac.za/Pages/emaildisclaimer.aspx

[Neil Daniels]

Correct me if I am not understanding correctly but for each replicate, it looks like maxent generated an average, min, max and stdev

The fact that there is only one average, min, max and stdev for all the ten replicates means that maxent created an average map for the each of these statistics ie. average, min, max and stdev?

Kind regards

Neil Daniels

[Neil Daniels]

One last question: What is the max amount of replicates you can use in maxent

I was going to use 100. But I have not seen anyone in academic literature use this value. most people use values like 10 and 15.

Is there a reason why people don't use 100 replicates?

Kind regards

Neil Daniels

[Samuel Veloz]

If you run 10 replicates, the value in each pixel is: avg= the average for that pixel across the 10 replicates; min = the minimum value for that pixel across the 10 replicates, etc. 

I don't think there is any fixed limit on the number of replicates. However, computation time would be one limitation. More practically though, you would need to have a large sample size of your occurrence data to have 100 replicates. Is your sample size large enough to create 100 unique occurrence sample size data sets? If not, why bother? In theory the background sample could change in each replicate but you should be selecting a background sample size that gives a reasonable estimate of the available environmental space so this shouldn't change that much, if at all, in each replicate.

Sam

--
You received this message because you are subscribed to the Google Groups "Maxent" group.
To unsubscribe from this group and stop receiving emails from it, send an email to maxent+un...@googlegroups.com.
To post to this group, send email to max...@googlegroups.com.
Visit this group at https://groups.google.com/group/maxent.
For more options, visit https://groups.google.com/d/optout.

[Neil Daniels]

Hi Sam 

Ok thanks for the info

My sample sizes are not that (max is about 700 for one sample)

For the background points, I defined my background by creating ascii files that contains the areas in which my samples occur in

I suppose when I do this, I should specify it in the max number of background points option in the settings tab? Instead of using the default value of 10000 max background points?  

Kind regards

Neil Daniels

To unsubscribe from this group and stop receiving emails from it, send an email to maxent+unsubscribe@googlegroups.com.

To post to this group, send email to max...@googlegroups.com.
Visit this group at https://groups.google.com/group/maxent.
For more options, visit https://groups.google.com/d/optout.

--
You received this message because you are subscribed to the Google Groups "Maxent" group.

To unsubscribe from this group and stop receiving emails from it, send an email to maxent+unsubscribe@googlegroups.com.

To post to this group, send email to max...@googlegroups.com.
Visit this group at https://groups.google.com/group/maxent.
For more options, visit https://groups.google.com/d/optout.

[vasudha chaturvedi]

Hye everyone, 

I am currently doing a project and i am facing few difficulties could you please help me out in solving my issues.

I would be really grateful to you all.

 

 These are the following questions-

1-For taking out Pearson coefficient correlation should the x and y sample size be same? I have Bioclimatic variables 1 and 12,land cover area in sq kms, human footprint,night time light data, area of rivers and roads also in sq kms and i have to calculate correlation between all of them. Which one should be dependent variable and which one should be independent variable?

2- I have two raster images of supervise classification 1st image showing water,river sand and forest area and the 2nd image showing agriculture,settlements and tea plantations. I had to calculate grid wise area for these two images so i did it but zonal-tabulate area and it gave me an output as so how much of forest,water and others features lies in that particular zones for those two different images. Now after calculating the area in excel for the two images i have to produce one vector map then a raster map to showing forest,agriculture,tea plantations,river sand and settlements in that one raster image. How to do it sir?

I would be really obliged if my problems are sorted.

Thanking You

With Warm regards