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How do I do error bars on excel/Microsoft??

Pickle
Original post by TheonlyMrsHolmes
Pickle


Are you asking to be beaten with a fish?
Original post by bluemadhatter
Are you asking to be beaten with a fish?


:loveduck:
Reply 4

Spoiler


From the Microsoft Office website, Idk if this makes any sense to you I have very little experience with excel
(edited 8 years ago)
Original post by bluemadhatter


If this is a new version of Office, with the chart selected, click on the "Design" tab under the "Chart tools" section of the ribbon, then click "add chart element" (on the left hand side of the screen) and then click "error bars". If your errors are absolute then click "standard error", if it's percentage then click "percentage error". Error bars will then appear. To modify them, right click on them in the chart and press "Format error bars". You can then ether apply a fixed absolute error to all, a fixed percentage to all, or you can apply a custom absolute error to each by clicking on "Custom" and then "Specify value". Type in the +/- absolute errors next to your data series in excel, then select the range of values and it'll automatically apply that.
Original post by Plagioclase
If this is a new version of Office, with the chart selected, click on the "Design" tab under the "Chart tools" section of the ribbon, then click "add chart element" (on the left hand side of the screen) and then click "error bars". If your errors are absolute then click "standard error", if it's percentage then click "percentage error". Error bars will then appear. To modify them, right click on them in the chart and press "Format error bars". You can then ether apply a fixed absolute error to all, a fixed percentage to all, or you can apply a custom absolute error to each by clicking on "Custom" and then "Specify value". Type in the +/- absolute errors next to your data series in excel, then select the range of values and it'll automatically apply that.


Sorry I meant range bars, is it the same thing though??
Original post by bluemadhatter
Sorry I meant range bars, is it the same thing though??


Yep same thing! So for each of "dark" and "light", you need to basically calculate the difference between the value you've used and the maximum, and the value you've used and the minimum.

Look at this...



So here, the Minimum and Maximum columns are the actual minimum and maximum (i.e. the range), the "Min" column is mean-min and the "Max" column is max-mean. You want to do Add Chart Element > Error Bars > Standard error, right click on the bars and press format error bars, select custom and then specify value. Then under the Positive Error Value, select the "min" column and for the Negative error value, select the "max" column (click the little button next to "positive error value" and then click and drag).
Original post by Plagioclase
Yep same thing! So for each of "dark" and "light", you need to basically calculate the difference between the value you've used and the maximum, and the value you've used and the minimum.

Look at this...



So here, the Minimum and Maximum columns are the actual minimum and maximum (i.e. the range), the "Min" column is mean-min and the "Max" column is max-mean. You want to do Add Chart Element > Error Bars > Standard error, right click on the bars and press format error bars, select custom and then specify value. Then under the Positive Error Value, select the "min" column and for the Negative error value, select the "max" column (click the little button next to "positive error value" and then click and drag).


http://prntscr.com/ac3nwk

it doesn't have add chart element ??
Original post by bluemadhatter
http://prntscr.com/ac3nwk

it doesn't have add chart element ??


Okay I think your version is a bit different, have a look at this....
Should be the same process once you've managed to actually add the error bars.
Original post by Plagioclase
Okay I think your version is a bit different, have a look at this....
Should be the same process once you've managed to actually add the error bars.


http://prntscr.com/ac3sz0
http://prntscr.com/ac3t46

did I format the minimum and maximum column wrong...

IDK :cry2:
Original post by bluemadhatter
http://prntscr.com/ac3sz0
http://prntscr.com/ac3t46

did I format the minimum and maximum column wrong...

IDK :cry2:


Okay well you've managed to add error bars so that's good. The problem is that you've now told excel to actually plot the minimum and maximum things as columns which is not what you want to do. When you're getting Excel to actually plot the graph, only select the mean values.

The way error bars work in Excel is that it uses absolute error since this is the way you'd most commonly get error in scientific experiments. It's still possible to plot ranges but it just means we've got to do an extra step. Rather than telling Excel to explicitly plot the error bars between a minimum and maximum value, you've basically got to tell excel to plot error bars x units below your mean and y units above your mean.

So say our mean is 10, the minimum is 7 and the maximum is 12, our negative error value needs to be 3 (10-7) and our positive error value needs to be 2 (12-10).

If none of this making any sense then you're very welcome to PM me your data and I'll put it into Excel for you.

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