The Mathematical Relationship between Model Complexity and Bias-Variance Dilemma

Most data science enthusiasts will concur with the claim - the ‘Bias-variance dilemma suffers from analysis paralysis’, as there is an immense literature on the concept of Bias-Variance, its decomposition, derivation, and its relationship with model complexity. Perhaps, we have crammed to the best of our abilities that simple models exhibit high bias and complex models experience low bias. Have we ever wondered why?

Some may choose to ignore this by proclaiming it to be just another question. But, …

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