#median of the probability density function shown

1 messages · Page 1 of 1 (latest)

pulsar glen
gritty walrus
# pulsar glen

If the PDF is $f(x)$ for $x>0$, and the median $m$ can be found in this way
$$\int_{0}^m f(x)=0.5$$

steady capeBOT
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! 拉夫

pulsar glen
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how would I do it with the piecewise function?

gritty walrus
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Have you find the equations yet?

pulsar glen
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1/3x and -1/2x

gritty walrus
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Alright so

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Integral is nothing but

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Area under the curve

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Agreed?

pulsar glen
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yes

gritty walrus
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So

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From 0 to 6, the area we have is

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0.5 times 6 times 0.2

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,calc 0.560.2

steady capeBOT
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Result:

0.6
gritty walrus
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That's more than 0.5

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Which means the median lies somewhere before 6

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Does that make sense?

pulsar glen
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ye

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yes

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oh i see now

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so f(x) would just be 1/3x

gritty walrus
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Which means that now we know which piece of the puecewise to integrate:)

pulsar glen
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thanks a lot

gritty walrus
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You may have to first integrate from 0 to 6

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And then 6 to some other number m

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To find the median

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But in this case it was not needed

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Does that make sense why?

pulsar glen
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if the median is in the second half?

gritty walrus
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Correct!

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If you are lucky

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And the visuals are correct

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You can figure out where the median lies

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By looking at the skewered graph

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Thats more of a lucky thing tho

pulsar glen
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ok thanks