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I want to improve/adjust/comprehend the formula (see below) that was used in my previous question: Transferring flows (connections + values) between polygons for calculating flow values of mobile data respecting the spatial/geographic gist.


formula

where
Flux - absolute value that is conveying
s_I_A - area of feature 'A' inside a cell 'I'
S_I - area of a cell 'I'
s_II_B - area of feature 'B' inside a cell 'II'
S_II - area of a cell 'II'


On the image below, there is a transfer of a value 100 from the cell 'I' to cell 'II'.

example_of_calculation


My question which factors can alternatively be used, besides the $area, in the formula for achieving better results in calculating the new flow value between feature 'A' inside a cell 'I' & feature 'B' inside a cell 'II'?

Moreover, I will be glad if someone can illuminate the non-meaningfulness/meaningfulness of this formula.


Aim: To compare new values from another source with values that are already known.


Besides the $area, I also own

  • addresses where inhabitants live
  • number of inhabitants per each address
  • thematic layers as polygons, e.g. Forest, Green areas, Streets, Buildings, Water etc.

From the above factors, I tried using the ratio of the area without forest, the number of inhabitants, and the number of addresses. I have access to QGIS 2/3, Python, R.


I previously tried asking it as Transferring values between polygons based on point criteria in QGIS? , however, at this moment I suspect that it was too broad and I did not show enough of my own contribution.

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+50

I think for translating information between a grid and units without other data, the main supposition is the data is evenly spatially distributed and you just have to apply the New Flux formula of your post, and sum all grids values that intersect units.

After, if data in grid is related to people houses (for example) and you have in possession houses location, you can see houses distribution into a specific grid cell and if this cell is cut by a unit, you can affect a proportion to the final flow calculation.

It will reflect more the reality IMHO.

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