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I measured some voltage values ($x$) and some corresponding frequencies ($y$). I know that the voltage can only be measured within an uncertainty $\Delta x$. And the uncertainty of $y$ shall be $\Delta y$.

Now I'm interested in the slope of the regression line and analyze it using root (the statistics tool). I used $x$- and $y$ error bars. Root returns an Error on the slope ($\chi^2$-Method).

Is this the final error on the slope or do I have to make some further propagation of errors?

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Perhaps would be a better home? – Qmechanic Feb 2 '13 at 21:18
did not know about this one - good idea, if a mod could move it… :-) – Vincent Feb 2 '13 at 21:22
paging the Reverend Bayes ... call for you on line 1 – EnergyNumbers Feb 2 '13 at 21:24
somehow I'm not able to directly apply the Bayes' Theorem in this case, perhaps you might give me a hint :-) – Vincent Feb 2 '13 at 21:37
This would be better on Stats.SE if you are primarily asking about the method or on SciComp.SE if you are primarily asking about the tool. Let me know which you prefer and I'll ask the mods if they want it (Stats in particular may already have a version...). – dmckee Feb 2 '13 at 22:11
up vote 0 down vote accepted

Assuming that you mean ROOT,1 and that you fit to a TGraphErrors, then you are done.

1 First time I've heard it described as "a statistics tool" though it will do a passable job in that context.

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yep, I meant that root and that TGraphErrors-Class :-) – Vincent Feb 2 '13 at 22:07

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