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Topic summary

Correlation in a self-tracked dataset: what it can support

This is a generated summary. It shows the 9 most-liked posts from a topic of 167, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.
OO
orbitrap_olaTL3Mass spectrometrist20 Aug 2024#7
g.tamm, post #6: Correlation is a good example of a question where the honest answer is boring and the interesting answers are unsupported. I would go with boring. Go to post

P-values and significance: p<0.05 means the data would be surprising if the null hypothesis were true, not that the null hypothesis is false. A non-significant p-value does not mean "no effect".

Two sources, same conclusion, and I could not rule out that one copied the other.

31 likes in reply to #6 23mo
BK
b.kowalskiTL220 Aug 2024#11
MSaarinen, post #9: Where I would push back on the correlation consensus is the confidence, not the direction. The direction looks right. The confidence is borrowed. Go to post

Taking post #8 at face value and following it one step further.

Rounding and significant figures carry information about precision. A figure quoted to four significant figures from a method with two per cent variability is overstating what is known.

29 likes in reply to #9 23mo
MG
m.guerreroTL221 Aug 2024 · edited#25
MSaarinen, post #9: Where I would push back on the correlation consensus is the confidence, not the direction. The direction looks right. The confidence is borrowed. Go to post

Two people in this thread mean different things by correlation and are disagreeing about the definition while believing they are disagreeing about the facts. Worth pausing to define it.

31 likes in reply to #9 23mo
MO
m.onwukaTL221 Aug 2024#39
g.pemberton_uk, post #30: Number needed to treat: how many people need to be treated to prevent one bad outcome or achieve one good outcome. More intuitive than relative risk reduction. Reading it again, the caveat matters more than the finding. Go to post

Percentages of small denominators should be reported with the denominator. Two out of three is not sixty-seven per cent in any useful sense.

For what it is worth, the same held on the two occasions I checked.

32 likes in reply to #30 23mo
RE
r.ekstromTL223 Aug 2024#67
NHuddleston, post #26: Building on post #23 rather than restating it. A methods point on correlation rather than a substantive one: if the comparison is not like for like, the difference you are measuring is the difference in method. Go to post

The honest answer on correlation 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.

31 likes in reply to #26 23mo
AC
a.coelhoTL224 Aug 2024#93
i.boateng, post #15: Correlation between two derived quantities that share a component is partly artefactual. It is a common trap in analyses of ratios. Go to post

Post #91 answers the question as asked. The question underneath it is different.

Number needed to treat: how many people need to be treated to prevent one bad outcome or achieve one good outcome. More intuitive than relative risk reduction.

28 likes in reply to #15 23mo
AV
a.villalobosTL224 Aug 2024#99

Same experience here, different supplier, so it is at least not unique to one of them.

29 likes 23mo
AK
a.kirchnerTL225 Aug 2024 · edited#125
e.kuipers, post #4: Following this. I have the same question and no better information than the first post. Go to post

Baseline imbalance in a randomised trial is expected by chance and adjusting for it post hoc is a choice that should have been pre-specified.

30 likes in reply to #4 23mo
NK
n.kaufmannTL226 Aug 2024#165
n.kuusela, post #8: Effect sizes: the magnitude of a difference, not just whether it is statistically significant. A difference that is significant (p Go to post

On correlation, I would rather understate and be corrected upward than overstate and be quoted. That is a house style here and it is a good one.

29 likes in reply to #8 23mo

Read the full topic (167 posts)

This topic was closed 45 days after the last reply. Closing is automatic for quiet topics so that a settled answer does not collect new questions underneath it. If you have a follow-up, open a new topic and link back to this one — that keeps both readable and gives your question its own title.
Moved from N-of-1 designs by t.vasquez. Category placement is not obvious from outside and getting it wrong is expected. This topic will get better answers here. The move is recorded in the public log citing R7.

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