Genuine question rather than a rhetorical one: has anyone here actually observed Start, as opposed to read about it? The thread is long and I cannot tell.
Why the Start Here categories exist, and what they are not for — that is the question, and I have not found it answered plainly anywhere I have looked.
Collecting what is known about Start in one place, because it is currently spread across a category, two tag pages and a thread that is hard to find.
This is a summary rather than new work, and I have attributed each part to where I found it.
The tag pages are usually a better entry point than the categories for a first read. A tag cuts across categories, so following one shows you how the same subject is treated by the analytical people and the practical people at once.
Old habit: I write down the expected answer before I calculate it.
One more thing on Start that took me far too long to see: the two figures people quote are not measuring the same quantity. Once you notice that, the apparent contradiction disappears.
The Lounge is a real category rather than a dumping ground. The sourcing rule still applies there, which surprises people, but the register is looser and nobody minds a digression.
Start is a question about a distribution, not about a value, and treating it as a value is what produces the confident wrong answers.
Marked solutions are the site's way of saying that someone asked a good question and someone else gave an answer that actually worked. It is not a competition and it does not appear on your record — it is just how the site learns which topics stay useful six months later.
Adding this to the thread rather than to the wiki, because I am not confident enough for the wiki.
The honest answer on Start is that it depends, and the useful part is the list of what it depends on. Four items, in rough order of how much they matter.
Most people get the first two right and then argue about the fourth.
I read the earlier replies on Start twice before writing this, because I had assumed the opposite and wanted to be sure I was disagreeing with what was said rather than what I expected.
The category structure looks heavier than it is. There are twenty top-level categories and you will use three of them. Find those three, mute the rest for a month, and come back to the others when a question sends you there.
None of the above is medical advice and I am not qualified to give any.
A methods point on Start rather than a substantive one: if the comparison is not like for like, the difference you are measuring is the difference in method.
Start is well covered in the tag pages, and the older discussions are better than the recent ones because they were argued out properly. Worth twenty minutes before adding to this one.
Marking my uncertainty on Start explicitly. I am confident about the direction, much less confident about the size, and not confident at all that it generalises past the case in the first post.
Asking as the newest person in the thread: is there a canonical order to read the documentation set in? I have been going alphabetically and that is clearly not it.
I would call that likely rather than established.
The failure mode on Start is boring rather than dramatic. It is almost always the step everyone assumes was done correctly because it is too simple to get wrong.
The Lounge is a real category rather than a dumping ground. The sourcing rule still applies there, which surprises people, but the register is looser and nobody minds a digression.
I would put this at better than even and not much better.
Practical answer on Start, since the theoretical one is upthread: do the simplest check first, write down the result, and only then decide whether the complicated explanation is needed. It usually is not.
What I can speak to on Start is narrow, so I will keep it narrow rather than generalising from it. Beyond that boundary I do not know.
Quietly grateful for the plain phrasing. Not every thread gets that.
The Lounge is a real category rather than a dumping ground. The sourcing rule still applies there, which surprises people, but the register is looser and nobody minds a digression.
Muting is under-used here. A category you mute stops appearing in Latest for you, and you can unmute it in a second. Most long-term members read four or five categories and mute the rest.
I would want to see it done twice before believing it once.