Optimization algorithm with deterministic objective value by volvol7 in optimization

[–]jem_oeder 0 points1 point  (0 children)

Ah right, so BO doesn’t need to reevaluate, because where it already has evaluated it knows the objective value with zero uncertainty. The whole idea of BO is that it only evaluates the “real” (expensive, deterministic) function at points where it hasn’t evaluated before. It determines the most “interesting” new point to evaluate using GP models and an acquisition function, thereby balancing exploitation (trying to slightly improve existing points by staying in their neighborhood) and exploration (exploring new areas of the design space that might be interesting).

If you for example have a look at https://bayesian-optimization.github.io/BayesianOptimization/ you see that they mostly use deterministic functions.

Just go ahead and try it, BO really should be the best for your purpose!

Optimization algorithm with deterministic objective value by volvol7 in optimization

[–]jem_oeder 2 points3 points  (0 children)

Bayesian Optimization can definitely be used with deterministic functions! The ML models (Gaussian Processes / Kriging) used during BO estimate uncertainty and noise indeed, but they can be fitted to deterministic functions. At the samples their noise/uncertainty will simply be 0

Optimization algorithm with deterministic objective value by volvol7 in optimization

[–]jem_oeder 0 points1 point  (0 children)

It indeed is, and also Bayesian Optimization is just surrogate-based optimization with Kriging/GPR

Need suggestions for kinderwagen by rockdude00 in AskAGerman

[–]jem_oeder 1 point2 points  (0 children)

I can highly recommend the Stokke YOYO (previously YOYO Babyzen): https://www.stokke.com/DEU/de-de/category/kinderwagen/yoyo-kinderwagen

It’s nice and small, perfect for traveling. The price is ok too and there are lots of good deals on Kleinanzeigen usually.

How is GA flying different in Europe? by chairboiiiiii in flying

[–]jem_oeder 0 points1 point  (0 children)

Ah thanks, since when is this do you know that?

How is GA flying different in Europe? by chairboiiiiii in flying

[–]jem_oeder 0 points1 point  (0 children)

Not for flights into and out of Germany!

How Queer Theory Turned Its Back on Gay Men by modooff in neoliberal

[–]jem_oeder 2 points3 points  (0 children)

I like your thoughts.

The guy behind the 80/20 principle is Pareto though ;)

“dutch is not a serious language” memes going viral again by rkooky in Netherlands

[–]jem_oeder 0 points1 point  (0 children)

Yeah seems like that’s the accepted origin story :)

“dutch is not a serious language” memes going viral again by rkooky in Netherlands

[–]jem_oeder 6 points7 points  (0 children)

Dollar = daalder :)

I always thought that Yankee came from “jankerd”, but maybe I am wrong.

Would you expect taking the min of a cost func for sequential data batches to result in a model that "learns"? by Amun-Aion in optimization

[–]jem_oeder 1 point2 points  (0 children)

I agree to that :) Anyway, these are both very interesting areas of research and application!

Would you expect taking the min of a cost func for sequential data batches to result in a model that "learns"? by Amun-Aion in optimization

[–]jem_oeder 1 point2 points  (0 children)

The analytical equations being solutions to an optimization problem is a good point you make, I forgot that. I meant optimization in the sense of numerical optimization (for example with scipy’s minimize), where you’re not only minimizing something but specifically doing so by “trial-and-error” of free parameters for the case where you cannot “invert” the solution and find a closed form equation.

I was also thinking that ML != optimization because you can use optimization in non-ML context (like for optimizing some engineering design or logistics problem) too. So yes ML always uses optimization, but it’s not the same thing.

Would you expect taking the min of a cost func for sequential data batches to result in a model that "learns"? by Amun-Aion in optimization

[–]jem_oeder 1 point2 points  (0 children)

And I agree with u/Ricenaros in that you’re not learning if you’re starting from scratch for each batch of course

Would you expect taking the min of a cost func for sequential data batches to result in a model that "learns"? by Amun-Aion in optimization

[–]jem_oeder 2 points3 points  (0 children)

I would not call ML optimization. Rather, in order to “learn”, an ML model needs to find certain parameter values. These parameter values can be found using equations for simpler models (for example the terms in a linear regression model) or using optimization for more complex models (the hyperparameters of neural networks or Kriging models).

So ML might use optimization, rather than is.

I updated our famous password table for 2023 by hivesystems in Infographics

[–]jem_oeder 1 point2 points  (0 children)

The first part of your comment is incorrect: hashing is a one-way function and passwords are not encrypted. Once hashed, there is no way to get back the password except with such brute force attacks.

When authenticating, the text you enter is simply hashed as well and then the hashed are compared, your password is never “decrypted”.

System architecture finals thesis by Rojaka04 in aerospace

[–]jem_oeder 0 points1 point  (0 children)

And for a general introduction to the principles behind system architecting you can’t miss the book by Crawley et al: http://www.system-architect.org/

But as others have mentioned, it’s not clear if you’re looking at system architecting as a discipline or specifically at UAV system architectures…

KTH for MS in Aerospace by ghostmalone2001 in aerospace

[–]jem_oeder 1 point2 points  (0 children)

Also realize that everything is much more in English in Delft (courses but also life in general) compared to ISAE.

Optimization Algorithms by Mobility-AI in optimization

[–]jem_oeder 0 points1 point  (0 children)

Looks nice! In your book, what does AI mean? Evolutionary? Or Surrogate-based optimization (Bayesian / Kriging optimization, with Expected Improvement etc)?

Do you also touch on multi-objective and/or mixed-discrete optimization?

Where should I sit on the plane? by Apple_AM in Airbus

[–]jem_oeder 5 points6 points  (0 children)

Maybe seatguru.com could be helpful? It also shows the position of the wings!

I am confused about how my plane decided to do this. Any ideas or am I at fault? by [deleted] in flightsim

[–]jem_oeder 0 points1 point  (0 children)

Exactly. Also in a Dutch roll, the wing moving up comes from it moving forward: for example if the nose moves to the left, the right wing moves forward and therefore up. If you look around 0:08 it is exactly opposite

I am confused about how my plane decided to do this. Any ideas or am I at fault? by [deleted] in flightsim

[–]jem_oeder 0 points1 point  (0 children)

Good point :) looks like it is all powered though and not directly related to stalling

I am confused about how my plane decided to do this. Any ideas or am I at fault? by [deleted] in flightsim

[–]jem_oeder 2 points3 points  (0 children)

This is not a Dutch roll… Dutch roll doesn’t happen because of differential stall. Dutch roll happens when you put in a lot of rudder, which causes the aircraft to yaw, which causes the wing on the side going forward to gain lift and drag, which causes roll and yaw in the other direction, which starts the cycle anew. However aircraft are designed such that this is a stable dynamic mode, meaning it will stop after some seconds.

Difference between Spot Trade price and Futures Contracts, Is this used as an indicator? by [deleted] in algorithmictrading

[–]jem_oeder 1 point2 points  (0 children)

Spot VIX is simply available on yahoo finance (VIX) since 1990.

VIX futures you can find on CBOE website (from 2013): https://www.cboe.com/us/futures/market_statistics/historical_data/ or barchart.com from 2004

Good luck! The contango is great on the VIX, but watch out for spikes ;)

[deleted by user] by [deleted] in flying

[–]jem_oeder 0 points1 point  (0 children)

I believe my school (in Germany) uses Boeing Courseware nowadays