←back to thread

Two undersea cables in Baltic Sea disrupted

(www.cnn.com)
577 points mooreds | 3 comments | 18 Nov 24 14:31 UTC | HN request time: 0.933s | source
Show context
staplung ◴[18 Nov 24 20:22 UTC] No.42176496[source]▶
It's worth mentioning that cable breakages happen quite often; globally about 200 times per year [1] and the article itself mentions that just last year, two other cables and a gas pipeline were taken out by an anchor. The Gulf of Finland is evidently quite shallow. From what I understand, cable repair ships are likely to use ROVs for parts of repair jobs but only when the water is shallow so hopefully they can figure out whether the damage looks like sabotage before they sever the cable to repair it. Of course, if you're a bad actor and want plausible deniability, maybe you'd make it look like anchor damage or, deliberately drag an anchor right over the cables.

Cable repairs are certainly annoying and for the operator of the cable, expensive. However, they are usually repaired relatively quickly. I'd be more worried if many more cables were severed at the same time. If you're only going to break one or two a year, you might as well not bother.

1: https://www.theverge.com/c/24070570/internet-cables-undersea...

replies(11): >>42177868 #>>42178949 #>>42179789 #>>42181124 #>>42181825 #>>42182141 #>>42182166 #>>42182377 #>>42183002 #>>42184314 #>>42187800 #
ValentinA23 ◴[19 Nov 24 00:38 UTC] No.42178949[source]▶
A 1 in 36 million chance for three breaks in one day.

https://mathb.in/80217

replies(8): >>42178979 #>>42178990 #>>42179288 #>>42179837 #>>42180330 #>>42181196 #>>42181536 #>>42186410 #
1. kqr ◴[19 Nov 24 08:36 UTC] No.42181196[source]▶
Why is this analysis focused on the Baltics? That's p hacking, given that it happened to happen in the baltics.

Let's instead say there are roughly 20 ocean regions we would post hoc consider "the same". Now, given a breakage, what is the probability of at least two more in the same region and day? This is a Poisson distribution with lambda=200/365/20. The probability of two more independent breakages is 0.04 % for that specific day.

But again, picking a specific day would be p-hacking. Zooming out, an event that rare is expected to happen every seven years or so.

Now, "every seven years" is a far cry from "1 in 36 million." Whenever you get crazy p values like that, there is often an error or overlooked assumption in the analysis.

----

If you like this sort of thing, have a stab at forecasting competitions! I can recommend the Metaculus Quarterly Cup. The current one is in full swing so use the remaining 1.5 months of the year to practice and then you're set for when the January edition starts.

replies(1): >>42184329 #
2. ValentinA23 ◴[19 Nov 24 15:17 UTC] No.42184329[source]▶
I see, this was in fact what I had in mind. The maths I posted represent the horizon of my knowledge in probability and was surprised how well o1-preview was able to output correct numerical calculations.

Having said that how would the odds look like if we factor in the fact the Baltic Sea is one of two zones with the most geopolitical tensions (along with Taiwan).

---

Thanks for the Metaculus recommendation. I was a bit disappointed in the lack of maths in the comments in general. Can you recommend something in the vein of Leetcode with various degrees of difficulty, from very basic to advanced problems ? I'm both interested in probability and statistics

replies(1): >>42184845 #
3. kqr ◴[19 Nov 24 15:55 UTC] No.42184845[source]▶
Something in thr vein of leetcode would be really useful to train people in forecasting, but given how subjective it is maybe difficult to pull off.