Can I Accurately Measure Temperature with 3 1/2 Digit Equipment?

AI Thread Summary
The discussion focuses on measuring temperature variations over a distance of 100 meters using 3 1/2 digit equipment, with a total of 55 measurements taken. The user has calculated the mean, standard deviation, and standard error for the data collected. The main concern is how to incorporate the equipment's accuracy of +/- 5% and +/-3 digits into the analysis. Suggestions include considering the propagation of uncertainty to accurately reflect the measurement's reliability. Resources were shared to help clarify how to integrate accuracy into the measurement process effectively.
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In an attempt to determine how the temperature varies over a distance of 100m, I have taken five temperature measurements for every 10 meters, for a total of 55 measurements. I have then, for each dataset of N=5, calculated the mean value, standard deviation and standard error. Finally, I've plotted the mean value with error bars in what I believe is the most accurate and informative way to represent this data (mean temperature on the y-axis, and distance on the x-axis).

So far so good I think, but how do I include the accuracy of the, say, 3 1/2 digit measurement equipment if it was specified as accurate to within +/- 5% and +/-3 digits?
 
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dlgoff said:
Where to start? Here maybe?

http://www.ni.com/white-paper/4439/en/
Thanks, but I didn't find what I was looking for at that url.

What I described above is basically a four step process (measure-->calculate mean-->calculate standard deviation-->calculate standard error) and I'm wondering at what stage it makes the most sense to take the 5% accuracy of the sensor into account. E.g., can I slap it onto the end of said four step process and simply increase the standard error by 5% (I'm guessing not, but I'm asking in order to clarify the problem).
 
Okay. You want Propagation of Uncertainty.

This looks good for that: http://www.rit.edu/cos/uphysics/uncertainties/Uncertaintiespart2.html#propagation

from http://www.rit.edu/cos/uphysics/uncertainties/Uncertaintiespart2.html
 
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