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On Melissa O’Neill’s PCG random number generator

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Re: On Melissa O’Neill’s PCG random number generator

#21

Post by dsacco »

CalChris wrote: post #11
pedrocr wrote: post #3

Earlier quoted context omitted.

Only if it turns out the work is actually good. If not this is exactly what should happen in peer review.

That is exactly what peer review should do, to determine whether the idea has merit. But that isn't what has happened. Peer review which is a cornerstone to the academic/scientific community stumbled on style and didn't get to merit.

I disagree, I think the peer review functioned exactly as it was supposed to.

Her paper doesn't pass the sniff test for me whatsoever when it comes to security analysis. She spent close to no time analyzing the primitives she introduced (and with no proofs or rigor!), meanwhile the thing is 58 pages because she takes the time to explain what "determinism" and "seeds" are to her audience.

"Exposition" is, in my opinion, a fully valid reason to reject a paper. I'm not going to sit and read your 60 page paper that could have been compressed to 10 pages if you just got to the point and assumed your audience understood the field well enough to assess your results. Rewrite it and send it back without the assumption that your audience needs to be reminded of everything they'd need to learn just to properly assess your result. It's not as though they rejected the paper on empirical grounds without a meritocratic review; they rejected it because they have a finite amount of time and (speaking as someone in the field) it's sort of annoying to read after page 10.

I think academia frequently gets lost in the ivory tower and loses touch with what an accessible paper looks like; this is not an answer to that, it's a swing in the other direction, where papers with truly novel results will suddenly be hundreds of pages and tens of pages of setup.

Re: On Melissa O’Neill’s PCG random number generator

#22

Post by wadkar »

bmm6o wrote: post #19

It sounds like an interesting result, I look forward to reading the paper more carefully. That said, it's clearly not written for an academic journal. Section 2.4.3 is entitled "The Importance of Code Size", and explains why shorter code is better. I think you can argue that some academic papers are excessively concise, but this is a 58-page paper about an RNG. It is clearly not a journal paper and has a ton of extra…

> I wonder why she didn't write [two] versions.

Because the reviewers took over 10 months to respond with a rejection mainly citing the length of the paper. And more importantly, "By that point, everyone who might have wanted to read it had almost certainly found it here and done so, so I saw little merit in drastically shortening the paper."[1]

She has updated the blog post which discusses all the nuanced details of the whole affair last month (2017-07-25)[2].

[1] http://www.pcg-random.org/paper.html [2] http://www.pcg-random.org/posts/history-of-the-pcg-paper.htm...

Re: On Melissa O’Neill’s PCG random number generator

#23

Post by lfowles »

marze wrote: post #18
Animats wrote: post #14

Here's the site for the random number generator.[1] It's basically a simple linear congruential random number generator (well known, but not very good) fed into a mixer. The mixer is new. Most of the analysis is about the LCG or the final output. The suggested mixer is just output = rotate64(uint64_t(state ^ (state >> 64)), state >> 122); That's simple, and the insight in this paper is that something that simple help…

>linear congruential random number generator (well known, but not very good) Relevant quotes from the paper: "But if you began reading the section with the belief that “linear congruential generators are bad” (a fairly widely-held belief amongst people who know a little about random number generation), you may have been surprised by how well they performed. We’ve seen that they are fast, fairly space efficient, and a…

> 247 nanoseconds is less than two days

Yes, yes it is.

For those just as confused as I was, replace all instances of 247 with 247

Re: On Melissa O’Neill’s PCG random number generator

#24

Post by dsacco »

lisper wrote: post #6
pedrocr wrote: post #3

Earlier quoted context omitted.

Only if it turns out the work is actually good. If not this is exactly what should happen in peer review.

You don't think the peer review process ever produces false negatives?

The peer review process absolutely produces false negatives, but that doesn't really change the fact that this paper doesn't need to be nearly 60 pages, doesn't sufficiently analyze one of its central premises (6.2.2 Security Considerations) and in general focuses on treatise and levity rather than rigor.

Re: On Melissa O’Neill’s PCG random number generator

#25

Post by fwdpropaganda »

Physicist here.

Off-topic

> And it is not even entirely clear what “really random” would mean. It is not clear that we live in a randomized universe…

At the quantum level it really is clear that we live in a really random universe. What's the meaning of really random? The outcome of a quantum process.

On-topic. Yeah, you have to know your audience. As OP mentions, just because the paper wasn't published doesn't prevent anyone from thinking about it and even building on it. On the other hand these scientific publications have styles and target audiences, and maybe she got rejected not due to lack of relevance or rigor, but because the paper didn't match the publication's non-scientific criteria for publication.

Re: On Melissa O’Neill’s PCG random number generator

#26

Post by dsacco »

the_stc wrote: post #17

As a general comment, I dislike deliberately obtuse writing in papers. In my current work, I came across a very in-depth survey of our industry (sex work). Excellent study, very helpful. But some of the sentences seemed to over-complicate the math. Example: "Consider the set P {p1, p2, ... pN} representing providers and the set C {c1, c2, ... cN} representing customers". I am pretty sure this kind of stuff is filler…

> On the other hand, maybe spending more than a line explaining what the birthday paradox is should be cut out and put in a backgrounder paper or appendix so that the paper can focus on the actual novel ideas.

That was my annoyance with the paper as well. Add to that explanations that amount to, "What even is determinism?" or "What's a seed?" and I'm unsurprised it's nearly 60 pages.

Re: On Melissa O’Neill’s PCG random number generator

#27

Post by dsacco »

lowmagnet wrote: post #4

I like this because she is a professor at Harvey Mudd. They took steps to make CS more inclusive, with great results. I appreciate her attitude on accessibility, which is in keeping with that institution's philosophy. That she ran into a paper wall doesn't bother her because she's openly publishing is even better.

Regardless of her attitude on academic accessibility, it is inappropriate for a paper introducing a novel primitive with proposed security considerations to spend the time explaining why determinism is a concern in functions dealing with randomness. This paper could have been 10 pages.

If you want to make your research more accessible, there are ways to do that without assuming that your reader is coming in from a dead start on the field.

Re: On Melissa O’Neill’s PCG random number generator

#28

Post by kurthr »

lfowles wrote: post #23
marze wrote: post #18

Earlier quoted context omitted.

>linear congruential random number generator (well known, but not very good) Relevant quotes from the paper: "But if you began reading the section with the belief that “linear congruential generators are bad” (a fairly widely-held belief amongst people who know a little about random number generation), you may have been surprised by how well they performed. We’ve seen that they are fast, fairly space efficient, and a…

> 247 nanoseconds is less than two days Yes, yes it is. For those just as confused as I was, replace all instances of 247 with 2 47

Hmmm... is HN removing ^carets?

Replace 247 with '2^47', Which is ~'1.28x10^14' or ~36 hours in ns.

Re: On Melissa O’Neill’s PCG random number generator

#29

Post by lfowles »

kurthr wrote: post #28
lfowles wrote: post #23

Earlier quoted context omitted.

> 247 nanoseconds is less than two days Yes, yes it is. For those just as confused as I was, replace all instances of 247 with 2 47

Hmmm... is HN removing ^carets? Replace 247 with '2^47', Which is ~'1.28x10^14' or ~36 hours in ns.

Hah. I used double asterisks, should have seen that coming in hindsight. Muphry's Law.

Re: On Melissa O’Neill’s PCG random number generator

#30

Post by mathperson »

the_stc wrote: post #17

As a general comment, I dislike deliberately obtuse writing in papers. In my current work, I came across a very in-depth survey of our industry (sex work). Excellent study, very helpful. But some of the sentences seemed to over-complicate the math. Example: "Consider the set P {p1, p2, ... pN} representing providers and the set C {c1, c2, ... cN} representing customers". I am pretty sure this kind of stuff is filler…

are you joking? That is your example of abstruse mathematical notation? Some variables with names?!
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