Why the Q1 and Q3 is different from what I think?

Question

I have a very confusing question about quantile. I have a sample here and its Q1 and Q3 should be like this: But when I summary the vector in R I got a different result:

summary(A)
#>    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
#>    1.00    2.75    4.50    4.50    6.25    8.00

I got different results of Q1 and Q3. OMG what happened? Thanks many in advance.

score 2 · Answer 1 · answered Mar 18 '20 at 00:20

2

There are lots of ways to calculate quantiles. Read the documentation

?quantile

And you'll see how R does it by default and what the other... 8 or so options are.

answered Mar 18 '20 at 00:20

Dason

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Wow thank you so much! But how can I tell which one is the best? Or most of the time which one people are going to use? (I'm just a beginner of statistics). – Chris Mar 18 '20 at 00:45
"best" isn't well defined. It depends on your situation and your data. – Dason Mar 18 '20 at 00:51
OK. Thank you so much! – Chris Mar 18 '20 at 01:56

Why the Q1 and Q3 is different from what I think?

1 Answers1