Change link to index diagram

docs/source/index.rst

@@ -5,7 +5,7 @@ Surrogate-assisted Bayesian validation of computational models
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 **BayesValidRox** is an open-source python package that provides methods for surrogate modeling, Bayesian inference and model comparison.
 
-.. image:: ./docs/diagrams/balance.png
+.. image:: ./public/diagrams/balance.png
    :width: 600
    :alt: Weighting model results against data with associated uncertainty, costs and sparsity