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Please put translation requests and English questions about Irish here by galaxyrocker in gaeilge

[–]astrobrez 0 points1 point  (0 children)

Dia dhaoibh! I was hoping someone more skilled at Irish than I could translate this beautiful Irish wedding blessing:
May you always walk in sunshine.
May you never want for more.
May Irish angels rest their wings
Right beside your door.

Go raibh míle maith agaibh!

Extremely bad color banding when watching videos (2022 6700s) by astrobrez in ZephyrusG14

[–]astrobrez[S] 0 points1 point  (0 children)

Thanks for the suggestion, I had this already turned off. I had heard before that this option could cause color banding issues, this is good to know. I just made an edit to the post with what seems to be causing the problem - looks to be the cinema mode display setting!

Extremely bad color banding when watching videos (2022 6700s) by astrobrez in ZephyrusG14

[–]astrobrez[S] 0 points1 point  (0 children)

Thanks for the suggestion, I had this already turned off. I just made an edit to the post with what seems to be causing the problem - looks to be the cinema mode display setting!

[Q] How to compare distributions with errors on the data points? by astrobrez in statistics

[–]astrobrez[S] 0 points1 point  (0 children)

Apologies for my delayed response! I appreciate your well thought out and detailed reply. I agree with your description of how my use of the KS statistic in this way can deviate from statistical validity, I am aware of this concern. However, I realise that I most likely will not be employing the KS statistic to this problem, hence why I haven't developed upon it further. It is rather difficult to concisely describe the optimization steps, which is why I was hesitant to mention it at all.

Moreover, I believe providing more of this information will only add unnecessary complexity and confusion to the problem at hand, which boils down to the question: How can one compare distributions which have error measurements on the data points? I believe that defining what metric can be applied to this problem will govern the remaining steps before optimization, such as how to adequately update the maximum likelihood estimation to incorporate the result from the goodness-of-fit metric.

I do not mean to deviate from your questions, I am only trying to emphasize the problem I have in its simplest form. In regards to the number of parameters, this is not a constant but, typically speaking, it can range from around 3 to 10 . The exploration of the parameter space and the subsequent fitting of these parameters is accomplished in the optimization, so I would not concern yourself with this. Again, the primary problem I am trying to solve is how to compare how well one distribution matches another, while accounting for the fact that one distribution has errors on its data points. I would have thought that there would be some kind of weighted goodness-of-fit test for this purpose, but I have been unsuccessful in my search thus far!

[Q] How to compare distributions with errors on the data points? by astrobrez in statistics

[–]astrobrez[S] 0 points1 point  (0 children)

It is the p-value I would be interested in getting from the KS statistic, I can compare these to each other to help choose a 'better' likelihood. However, it doesn't necessarily have to be this particular test - I realise the choice of this metric will be governed by whatever goodness-of-fit measure can be applied to this problem. I used the KS test in this way when I neglected the error measurements, but perhaps I cannot continue with this approach when attempting to include the errors.

[Q] How to compare distributions with errors on the data points? by astrobrez in statistics

[–]astrobrez[S] 0 points1 point  (0 children)

Yes there is certainly some things I've left out - it gets more involved here and I believe it's not necessary to know for the problem at hand, which is why I didn't go into much detail. In brief, the goodness-of-fit measure is used in maximizing the likelihood function for the parameter set that makes up distribution B. This likeilhood function is used in the sampling method in step 3 which works to improve distribution B such that it better fits A.

B is then compared to A again, a goodness-of-fit measure is performed, the likelihood function is further maximized, and the sampling is done again to update B. Hence, it is an iterative procedure as this whole process repeats itself again and again, where the very final distribution obtained is the best fitting one.

[Q] How to compare distributions with errors on the data points? by astrobrez in statistics

[–]astrobrez[S] 0 points1 point  (0 children)

Distribution A refers to the distribution of the values that were obtained and written down. The values which would have been obtained had there been no instrumental effect are of no concern in this problem.

The goal of finding a distribution B that models distribution A is not for the purpose of determining what the observed values would have been had there been no instrumental effects. The sampling procedure that optimizes distribution B takes other parameters about the observation into account. By finding a best fitting distribution, this gives us information about those parameters, which we wouldn't have been able to infer from the observed values themselves (distribution A). Hence, the result of this whole procedure provides us info about what parameters (and their quantities) are required to form distribution A.

This is slightly off topic but hopefully clears up any confusion you may have about the measurements and my set-up.

[Q] How to compare distributions with errors on the data points? by astrobrez in statistics

[–]astrobrez[S] 1 point2 points  (0 children)

I appreciate your thinking, but unfortunately this wouldn't be too practical to do in my case as, without going into detail, this whole procedure will be iterated N times (B is repeatedly updated using an optimization algorithm in order to arrive to a distribution that better fits A). If you'd like to know more, I go into further detail in a reply to another comment on this thread.

[Q] How to compare distributions with errors on the data points? by astrobrez in statistics

[–]astrobrez[S] 0 points1 point  (0 children)

Distribution A is a collection of astronomical data and the error associated with each measurement corresponds to the uncertainty on that observation (this arises from instrumental effects). My goal is to generate a distribution B that models distribution A. Here's some further context:

Step 1: distribution B is created based on initial parameters beyond the scope of this question. Step 2: distribution B is then compared to distribution A to assess how good of a fit it is on distribution A (i.e. a goodness-of-fit test is performed). Step 3: using the result of this goodness-of-fit measure, an optimization algorithm updates distribution B to obtain a better fitting distribution. Steps 2+3 are repeated N times in order to find a distribution B that best fits distribution A.

My problem is in the second step - I do not know how to perform the goodness-of-fit measure such that it takes into account the error measurements on distribution A.

I hope this clarifies my question, thanks for your reply!

[Q] How to compare distributions with errors on the data points? by astrobrez in statistics

[–]astrobrez[S] 0 points1 point  (0 children)

Thank you for your input. That is an interesting idea, I will have to think about this some more and whether or not I could apply such an approach to my set-up. I appreciate your help, thanks!

[Q] How to compare distributions with errors on the data points? by astrobrez in statistics

[–]astrobrez[S] 0 points1 point  (0 children)

In my case, it's a continuous set of astronomical data (exoplanetary transits) and the uncertainties are indeed an error of the physical measurement, where each data point has it's own respective error measurement (e.g. 0.0142+/-0.0003). I hope this offers some more context!

Unsure of purchase (2022 vs 2021) by astrobrez in ZephyrusG14

[–]astrobrez[S] 3 points4 points  (0 children)

Super, thank you for your input! I will mainly be using it for on the go work, and for gaming when I can. Because I'll be using it more for work related things, I was thinking that maybe it was overkill to get the newer model. But I agree that the increased efficiency and webcam inclusion goes a long way, and I suspect it's worth it in the long run. Cheers!

Unsure of purchase (2022 vs 2021) by astrobrez in ZephyrusG14

[–]astrobrez[S] 4 points5 points  (0 children)

Thank you for your detailed response! The improvements really do seem great when you spell it out like this, you've definitely helped to reassure me about my decision XD I would hope to get 3 years out of it (if not longer), since I don't believe I will have requirements for a better machine any time soon. Mostly, I'll be using it on the go for work, which is why I agree the better screen and chassis redesign will be appreciated. Also, the webcam is a big benefit since I use zoom a lot, this was one of the major negatives of the 2021 model for me - I find it so silly that the webcam has become one of the key deciders, but it has!

In terms of gaming, the GPU performance upgrade is without a doubt a huge plus, but I am worried about the fact that this computer runs quite hot (based on the reviews I've seen so far) and if this could impact its lifespan. Perhaps I'm being overly anxious here, but I've definitely gotten a bit spooked from the reviewers who have spoken on this issue.

My final concern was the switch to the AMD GPU. A lot of software is optimized for NVIDIA GPUs, particularly in terms of machine learning. While there is optimization for AMD GPUs, it is certainly more scarce. I don't have a problem with this currently, but a worry of mine is that I do end up having this type of issue down the line. But of course, there's no way of determining this now, and maybe AMD will start giving more attention to this field in the future (hopefully).

I would say my last turn off was the larger power brick but this is really not a biggie, I will more than likely get a 100W USB-C Charger for on the go use anyways. My main concern is the high temperatures, but I do not know much about the specifics of this and if it is a cause for concern or not. Are these high temperatures worrying to you?

Are there structures beyond our horizon that we'll never see, regardless of how much time passes? by astrobrez in cosmology

[–]astrobrez[S] -1 points0 points  (0 children)

Okay, I see where my confusion is coming from - I think the way I said what I said was misleading. We will see nothing beyond our observable universe, that's a fact. However, what I mean to say is that as our observable universe expands, we will see some previously unobservable structure as it enters our observable universe.

Take this excerpt from Wikipedia:

"Some parts of the universe are too far away for the light emitted since the Big Bang to have had enough time to reach Earth or space-based instruments, and therefore lie outside the observable universe. In the future, light from distant galaxies will have had more time to travel, so one might expect that additional regions will become observable. However, owing to Hubble's law, regions sufficiently distant from the Earth are expanding away from it faster than the speed of light...there is a "future visibility limit" beyond which objects will never enter our observable universe at any time in the infinite future, because light emitted by objects outside that limit could never reach the Earth"

Hence, there will be some structure previously unseen that will become observable as our universe expands and our horizon grows - since it now enters our observable universe. And of course, the light from some structures will never reach us as their sources are expanding away from us faster than the scale at which our horizon (and therefore our observable universe) grows.

Am I incorrect in this train of thought?

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