Determining Error Slope
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Springs Charge of an Electron Video Analysis Torque Rolling Objects Mechanical Energy Human Performance Old labs Extra Stuff Slope uncertainty Reports How to find the uncertainty in the slope This is an issue that I have how to determine uncertainty of slope not really addressed much. However, it is important enough that I talk about how to determine uncertainty of slope in excel it. In many labs, you will collect data, make a graph, find the slope of a function that fits that how to calculate error in slope excel data and use it for something. Well, what if need to find the uncertainty in the slope? How do you do that? There are a couple of ways you can do this, neither
How To Calculate Standard Error Of Slope
are absolutely correct. However, if you write a formal lab report and you find the slope you MUST find the uncertainty in it. Here is some sample data. Suppose I measure the diameter and the circumference of several roundish objects. Here is my data. So, I want to plot this and find a functional relationship between these two. With error bars, this is what it should look how to calculate standard error of slope coefficient in excel like: Now, I want to fit a linear function to this data. That should be ok, but what about the uncertainty? Method 1 - use uncertainty of data points I could get the ratio of C/d by just looking at each data point. This is not as good as the slope because the slope essentially uses all the data points at once. In this method, I am going to find the slope as normal. In Excel, you could fit a trendline. Or, you could draw a best fit line. Either way, I would get something like this (I did this in Logger Pro): This gives a slope of 3.28 (compare to pi = 3.14). I could get a better slope if I required the fitting function to go through the origin (0,0), but I am not going to do that. In essence, the slope is: But, what if I just use one set of data points? Then I could use propagation of error as usual. This would give Where the delta - slope represents the uncertainty in the slope. For this method, just pick the data pair with the largest uncertainty (to be safe) - although hopefully, it won’
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Finding Uncertainty In Slope
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Uncertainty In Slope Excel
Sports Travel Yahoo Products International Argentina Australia Brazil Canada France Germany India Indonesia Italy Malaysia Mexico New Zealand Philippines Quebec Singapore Taiwan Hong Kong Spain Thailand UK https://www2.southeastern.edu/Academics/Faculty/rallain/plab193/page1/page35/page36/page36.html & Ireland Vietnam Espanol About About Answers Community Guidelines Leaderboard Knowledge Partners Points & Levels Blog Safety Tips Science & Mathematics Physics Next How to find the slope % error, and the % difference when the x-axis is 5.0, y-axis is 4.0 and the x-axis is? 9.8, y-axis 34. Follow 1 answer 1 Report https://answers.yahoo.com/question/index?qid=20100525132645AAVOTXO Abuse Are you sure you want to delete this answer? Yes No Sorry, something has gone wrong. Trending Now Butch Jones Barack Obama Issa Rae Keith Zubchevich Infiniti Dealer 2017 Cars Jade Roper Patti Scialfa Psoriatic Arthritis Symptoms Cloud Computing Answers Best Answer: I'm not sure this CAN be answered. Are you leaving part of the problem out? Calculating the slope is pretty simple. The formula is y-y/x-x. That is, (34-4)/(9.8-5). The slope is thus 30/4.8 or just 6.25. Now, I know how to calculate percent error. The equation is: ((your result - accepted value)/accepted value) * 100 Noting that it is the absolute value of the difference between your result and the accepted value. However, what is the accepted value for this slope? That's what you need. After that, you can just plug the values in. In other words: ((6.25 - x)/x) * 100 = slope percent error Equation for percent difference: (x-x)/((x+x)/2) * 100 So, it's (9.8-5) divided by
Community Forums > Mathematics > Set Theory, Logic, Probability, Statistics > Dismiss Notice Join Physics Forums Today! The friendliest, high quality science and math community on the planet! Everyone who https://www.physicsforums.com/threads/estimating-error-in-slope-of-a-regression-line.194616/ loves science is here! Estimating error in slope of a regression line Page 1 of 2 1 2 Next > Oct 29, 2007 #1 Signifier OK, I have a question I have no idea how to answer (and all my awful undergrad stats books are useless on the matter). Say I make a number of pairs of measurements (x,y). I plot the data, and it looks how to strongly positively correlated. I do a linear regression and get an equation for a line of best fit, say y = 0.3x + 0.1 or something. The Pearson coefficient is very close to one, IE 0.9995 or so. Now, say that the quantity I am interested in is the slope of this line, that is (for the above equation) 0.3. I take all my measurements, get how to calculate the line of best fit, find its slope, and the slope is something I want. For example, with the photoelectric effect, maybe I measure stopping potential vs. frequency of light; the slope can be related to Planck's constant. Or something similar. The question I have is: how do I estimate the error (uncertainty) in this slope value I get? My professor said to use the "standard deviation in the slope," which doesn't sound sensible to me. I thought to myself: well, maybe it has to do with using the uncertainty in x and the uncertainty in y. But how would you combine these uncertainties to find the uncertainty in dy/dx? How does one estimate the error range for a parameter obtained from the slope of a line of best fit on a set of (x,y) data? Thank you so much, this one seems really important and I'm a bit disturbed I haven't the slightest idea what to do. Signifier, Oct 29, 2007 Phys.org - latest science and technology news stories on Phys.org •Game over? Computer beats human champ in ancient Chinese game •Simplifying solar cells with a new mix of materials •Imaged 'jets' reveal cerium's