What Could a Steeper Best Fit Line Than Maximum Line Mean in Graph Analysis?

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The discussion centers on the perplexity of a steeper best fit line compared to the maximum line in a graph analysis related to the Doppler Effect experiment. The user is advised that this anomaly may stem from overly small error bars, indicating potential measurement inaccuracies. It is emphasized that if the error bars are accurate, the system may not exhibit linear behavior. Participants suggest sharing the raw data in a machine-readable format, such as CSV, to facilitate further analysis.

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CrzCz
Hi guys so I have done a Physics EE but after plotting the graph, I encountered a very huge problem with my best fit, maximum, and minimum line... My best fit line is steeper than my maximum line! (Minimum line: Orange Maximum line: Grey Best fit line: Blue)

So the thing is, what does this mean? I don't even know what to say about my analysis or anything anymore.. Please help..
 

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From the looks of it, your error bars ## \Delta x ## might be too small. There can be measurement errors that aren't completely obvious. e.g. if a meter measures something with 3 decimal places doesn't mean you have 3 decimal place accuracy. ## \\ ## There is also the possibility that the system that was being measured does not have a straight line behavior, but assuming that it does, the error bars appear to be too small. If the error bars are indeed accurate, it would indicate the system does not obey that of a straight line in y vs. x.
 
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Why don't you show the data that you started with and then we can maybe suggest something.
 
magoo said:
Why don't you show the data that you started with and then we can maybe suggest something.

So the experiment that I did was for Doppler Effect... For the graph, the blue line is the data I got from the experiment and the orange line is the data that I got from calculations...
 

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The theoretical values are not relevant to your question, right? You are just asking about the three regression lines you got from the measurements.
Please post your measurements in a machine-readable form. I know PF doesn't allow .xls, for some strange reason, but you could use .csv as a text file.
Please also explain how you obtained the three regression lines.
 

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