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Francisco Francisco is offline
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Default New method for PERCENTILE & QUARTILE formulas

Dave,
That is not entire true, there are 2 methods. That is fine for certain
cases, however when it is necessary to take a value that belongs to the
series this method is not appropriated. The key is: "it has to belong". Excel
should allow me to fine tune this.

I have another example where Excel has the WRONG calculation:
{10,20,30,40,50,60,70,80,90,100}
What do you expect if you do =quartile(RANGE,3), Upper Quartile?
Yes, you will expect 75 as the Upper Quartile .... but surprise surprise
....Excel shows 77.5.
This is just plain wrong.

What I am saying is to extend NOT to replace the funcionality to have a more
appropiate calculation.

F

"Dave F" wrote:

50255 is the median of the sequence of numbers you give. A set of six values
does not have a median exactly equal to the value of any of the numbers.
Rather, it is equal to the third largest value plus the fourth largest value
divided by two.

Dave
--
A hint to posters: Specific, detailed questions are more likely to be
answered than questions that provide no detail about your problem.


"Francisco" wrote:

I see your point but this method does not work with large series.
The PERCENTILE value must be a number that belongs to the series.

We do tables of salaries and we need to show the salary that best represents
the MEDIAN or a QUARTILE. For example:
{$50000, $50001 $50010 $50500 $50501 $65000}
The right MEDIAN value is $50010 and Excel provides $50255, this is just
wrong. $50255 does not belong the series.

"BoniM" wrote:

=INT(PERCENTILE(A1:A10,0.5))

"Francisco" wrote:

I have a suggestion that we will be very useful for our company.
The way Excel calculate PERCENTILE and QUARTILE series is not appropiate for
discrete numbers.

My suggestion
At the moment =percentile(a1:a10,.05) gives 5.5 in the sequence
{1,2,3,4,5,6,7,8,9,10}. This is incorrect on discrete numbers.

Following the example above, I want to gather discrete numbers, i.e. "5" on
the series rather than "5.5". The same apply for QUARTILE formulas where a
second parameter is needed.
Add a Third parameter [optional] as follows:
- 0, default (as it currently works)
- 1, takes the inferior discrete number
- 2, takes the superior discrete number


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