Hi there,
I need some help with finding a separation value between two data sets.
I am trying to identify burned areas based on the values of pixels in Near Infra Red (NIR) and Short Wave Infra Red (SWIR) values registered before and after a forestry fire. There is a drop in NIR values and a rise in SWIR values between date 1 and date 2 when a forestry fire happens and a burned areas appears on the satellite image. This drop is caracterized through a index calculation (Relative Difference Normalized Burn Ratio - RDNBR). I want to find a limit between the RDNBR values of a burned area and the RDNBR values of a non-burned area in order to calibrate my model and to find all the burned areas in a large set of satellite imagery.
I visually identified two sets of pixels in my images: the first set (conIncendios) corresponds to pixels that where covered with forests in date1 and burned areas in date 2; the second set (sinIncendios) corresponds to pixels of forest in date1 and date2 (no change).
The result i get is two sets with different values but there is an overlapping between the two sets as show in this boxplot picture (first quantil of first set overlaps last quantil of second set:
My question is: Is there a way of calculating the best separation value between those two sets ?
I hope I didn´t forget anything useful in this explanation...
Thanks in advance,
I need some help with finding a separation value between two data sets.
I am trying to identify burned areas based on the values of pixels in Near Infra Red (NIR) and Short Wave Infra Red (SWIR) values registered before and after a forestry fire. There is a drop in NIR values and a rise in SWIR values between date 1 and date 2 when a forestry fire happens and a burned areas appears on the satellite image. This drop is caracterized through a index calculation (Relative Difference Normalized Burn Ratio - RDNBR). I want to find a limit between the RDNBR values of a burned area and the RDNBR values of a non-burned area in order to calibrate my model and to find all the burned areas in a large set of satellite imagery.
I visually identified two sets of pixels in my images: the first set (conIncendios) corresponds to pixels that where covered with forests in date1 and burned areas in date 2; the second set (sinIncendios) corresponds to pixels of forest in date1 and date2 (no change).
The result i get is two sets with different values but there is an overlapping between the two sets as show in this boxplot picture (first quantil of first set overlaps last quantil of second set:

My question is: Is there a way of calculating the best separation value between those two sets ?
I hope I didn´t forget anything useful in this explanation...
Thanks in advance,
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