How are percentiles calculated in Jamovi? I have searched high and low and I cannot find a clear answer.
When I request percentiles (25, 50, 75) for the follow set of data:
5
8
10
15
18
25
30
35
40
45
the output reports:
25th 11.3
50th 21.5
75th 33.8
The 50th percentile is pretty straightforward, but I am not sure what is happening for the 25th and 75th percentiles.
How are percentiles calculated?
Re: How are percentiles calculated?
hi,
jamovi uses the quantile function from R, which looks to default to "type 7" quantiles.
you can reproduce with the following R code:
quantile(c(5, 8, 10, 15, 18, 25, 30, 35, 40, 45))
cheers
jonathon
jamovi uses the quantile function from R, which looks to default to "type 7" quantiles.
- Screenshot 2025-01-13 at 10.09.32.png (16.36 KiB) Viewed 412 times
you can reproduce with the following R code:
quantile(c(5, 8, 10, 15, 18, 25, 30, 35, 40, 45))
cheers
jonathon
Re: How are percentiles calculated?
Thank you! I appreciate your response. This equation was a bit puzzling to me without knowing more about how the variables were defined.
The R documentation is great though and helped to fill in the gaps.
https://www.rdocumentation.org/packages ... s/quantile
The R documentation is great though and helped to fill in the gaps.
https://www.rdocumentation.org/packages ... s/quantile