QuKunLab / SpatialBenchmarking

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Rationale of calculating JS #25

Open Puriney opened 1 month ago

Puriney commented 1 month ago

Hello, I was wondering could you elaborate on the rationale of the way you calculate the JS score.

image

In the paper, it was splitting the predicted and observed prob into 2 halves and mixed together.

What about

$$JS=KL(\tilde{P_i}|P_i)$$

or

$$JS=KL(P_i|\tilde{P_i})$$

Many thanks.

Puriney commented 1 month ago

KL is asymmetrical (meaning that $$JS=KL(\tilde{P_i}|P_i)$$ and $$JS=KL(P_i|\tilde{P_i})$$ are different JS scores). Using the 'baseline' distribution is the key, therefore, mixing the two in the manuscript seems not appropriate to me. Using the observed spatial expression as the ground truth seems more reasonable to me.