Overfitting with Polynomials : deterministic noise

[Kevin]

I have some difficulty to understand the idea of deterministic noise. I think there are some disturbing contradiction with what we've seen with the bias-variance tradeoff, particularly with 50th order noiseless target exemple.

Chapter 4 state that:
- A 2nd order polynomial could be better than a 10th order polynomial to fit a 50th order polynomial target and it's due to the deterministic noise.

--> So I conclude that there is more deterministic noise with 10th order than with the 2nd order.

- Deterministic noise=bias

But we've seen with the bias-variance tradeoff, that a more complex model than an other have a lower bias.

Obvioulsy, I'm wrong somewhere, but where ?