Accuracy vs precision and biased vs. unbiased methods

[vlado]

I was recently dismayed to learn that many people assume that the term 'unbiased' means 'physically correct', and 'biased' - somehow physically inaccurate; while in fact, the relationship between the two terms is similar to the one between 'precision' and 'accuracy' as used in a scientific context. Unbiased calculations have great precision, but that does not imply anything about their accuracy (how close they are to the actual correct results). The reverse is also true - biased calculations can be quite correct (e.g. very close to the actual result), but typically somewhat imprecise.

There's some more visual information here:

http://honolulu.hawaii.edu/distance/...5/accprec.html

Best regards,
Vlado

[Neilg]

The decline in image quality from maxwell through the beta is a good example of this...

[dlparisi]

The decline in image quality from maxwell through the beta is a good example of this...

Not doubting you but can you post some images or a link, I'm kind of curious.

[Neilg]

It's fine now (and it wasnt a big drop anyway, if there was one), this was years ago - they released a build where they had managed to knock the rendertime down a hell of a lot, but people were saying the image quality had gone down too. It was still unbiased all the way through that though.

It was mostly just a nod to those that were on their forum around the time, which a fair few poeple from here were.

[Morbid Angel]

Well I also think people have misinterpreted biased and unbiased.
For me its quite simple: biased is exactly same as unbiased, in terms of math and calculation, the only difference is the bias uses interpolate for samples, whereas unbiased does not.

Maxwell on the other hand is a different story imo, it remains unbiased in the way of its sampling, though it uses a different kind of path tracing then beta did.
I honestly believe you can still get a solid image out of maxwell.
The point of maxwell however back in the day was: simplicity, fast setup and photo real quality. Now, its reversed: complex, very long setup, attempted photorealism is not as simple to achieve.
But ultimately is comes down to the artist. I think back in the beta days of maxwell there were a few very good artists around who produced those amazing images, who are not around anymore.

With current tools in vray, I can say with absolute certainty that any image created by maxwell or any other renderer can be also created by vray at 90-99% match. I have done so my self

[percydaman]

ya the biggest thing about maxwell back in the day, was the quality of the artists that were showcasing really their own talents, as much as the renderer itself.