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# box plots, help plz watch

1. Hey, I'm having some problems with one of my box plots. The lowest value is higher than the lower quartile, and because of this the left whisker goes back inside the box. What do I do???
2. (Original post by digideens)
Hey, I'm having some problems with one of my box plots. The lowest value is higher than the lower quartile, and because of this the left whisker goes back inside the box. What do I do???
That just can't happen, lower value is called so because it is the lowest of all the values, which a box plot can represent the lowest value at the far left hand side.

You've probably worked out the lower quartile wrong.
3. Actually I worked out the lower quartile from a cumlative frequency graph so I probably got that wrong.
4. (Original post by digideens)
Actually I worked out the lower quartile from a cumlative frequency graph so I probably got that wrong.
Well thats fair enough, but yes it wouldn't be that accurate, I recommend you work with the raw values, find the very lowest value, and very highest value, arrange the data in ascending order, and find middle value, hence find the second middle value (Q1) at the very left side, this is the lower quartile.

Work with > (n + 1) / 2 where n is number of values in the set, this value will be the middle value, then do the formula again, to find lower quartile.

If you need help with this, post the data values here.
5. Yeah I know what I'm doing now, thanx.

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