[kurtisc]

I've noticed a trend on BBC news.

'[X market/stock] slumps as [thing related to X] [does something]'

Yet when you go and look at the long-term graph, it's well within normal variance. There's no evidence they're connected at all. I'm sure it happens with other media providers too.

Why? Because they didn't have the numbers right, or just didn't check at all. Well, if I'd written a statement like that in an essay during my schooling, I'd be marked down for unsubstantiated claims at best or admonished for plagiarism at worst.

I find it irresponsible that the news rarely cites its sources beyond admitting they bought it from AP/Reuters. I believe it should be enough to prevent them being cited as a trustworthy secondary source until they at least have their justifications to a level that would be considered adequate by a high school history class. It's the only reason citogenesis happens on Wikipedia.

[buttcoinslol]

The problem is that "Sellers outnumber buyers as equity markets fall" and "Buyers outnumber sellers as equity markets post gains" are not compelling headlines.

As you've noted, financial news is post-hoc analysis. It is narrative-based, and not fact-based. Sometimes the narratives and facts coincide, though.

[rebuilder]

Those statements seem odd, as well. You can't really tell how many of either there are.

[Simon_says]

> "Sellers outnumber buyers as equity markets fall"

> "Buyers outnumber sellers as equity markets post gains"

And those statements aren't even necessarily true.

[lotsofpulp]

That’s how financial news has always been reported. They need to sell papers, and technically they’re just mentioning two things that happened to happen at the same time.

[yellowapple]

I think you're conflating whether or not there's correlation/causation with whether or not the result is significant. If a stock appreciates or depreciates at the same time that something related to that stock happens, a relationship between the two is not an unreasonable hypothesis.

Of course, there's still the matter of actually validating that hypothesis, and examining whether said hypothesis actually holds true or the coincident timing really is just coincidence and nothing more (or, indeed, if the timing really was coincident between the two events, e.g. whether or not the stock move happened before the event that allegedly "caused" it).

And of course, even if the event did cause the stock move, that's still a separate concern from the long term impact of that stock move. It could very well just be a temporary blip, or it could be a harbinger of some more significant change.

[labawi]

A nitpick: Markets are driven by beliefs and expectations not real-world events themselves. It may not be simple to follow the causation and timing.

[esoterica]

> Yet when you go and look at the long-term graph, it's well within normal variance. There's no evidence they're connected at all.

What a completely mathematically and financially illiterate thing to say. Whether or not a market move is within “normal” variance has nothing to do with whether or not it is clearly attributable to a particular economic event. If Jerome Powell says something about rates or Trump tweets something about tariffs and the market moves 1% in the exact minute that happens you can pinpoint the cause of the move with pretty high confidence even if 1% is not significant relative to the long term variance.

I’ve seen this bizarre sentiment propagated on HN before. A lot of people seem to think it’s never possible to identify the causes of market movements (even when obvious market moving news is released).

[kurtisc]

>long term variance

That's not a phrase I used. I'm sorry the sentiment upsets you; please don't conflate it with mine.