User talk:Steven J. Koch

UWLC2

It hurts that I wasn't included in this. Anyways. If you want to get into shape for the run for the zoo, maybe I could help. I need to build up some stamina and need to get to working out cardiovascularly. Can we collaborate somehow? Maybe with a competition or direct workout alliance?---Ant (forgot to sign)

no, thank YOU

I love the idea of using a wiki. Even if it is used to post photos of eyes and talk about the squiggly dots, which I have yet to notice, but I will make a point of it.--Bradley A. Knockel 10:06, 22 August 2007 (EDT)

Re: comments on Physics307L:People/Mondragon/Notebook/071003#Compilation_of_plots

Have you thought of a reason for that possible [math]\displaystyle{ \sqrt{counts} }[/math] weighting factor that you suggested may be missing in my chisquare fit? I looked at the article about Poisson distribution on wikipedia and I found what you may have been thinking. The standard deviation of a Poisson distribution with a mean [math]\displaystyle{ \lambda }[/math] is [math]\displaystyle{ \sqrt{\lambda} }[/math]. I don't think this has much to do with the uncertainty of a count. If I were to include an uncertainty in count, that uncertainty would have more to do with how fast our apparatus could react to an event, I think. If the equipment can only count reliably as fast as x counts per millisecond, the uncertainty would rise with an increase in count number, as the [math]\displaystyle{ \sqrt{counts} }[/math], but it would also increase with a decrease in bin size (dwell time).

I might analyze how this kind of error would effect data. It might also make a good experiment if there was some way to get the detector to detect things that happen a an adjustable constant rate rather than an average rate.

Where the [math]\displaystyle{ \sqrt{\lambda} }[/math] maybe should have come in my analysis was in that final plot. I used the error in my fits as error bars for the [math]\displaystyle{ \lambda }[/math]s. No, I did it right, the error bars are estimation of how uncertain the measurement (or calculation) of [math]\displaystyle{ \lambda }[/math]. No, the error bars are probably wrong, and the correct way to calculate it is the way you mentioned Dr. Gold taught. I should have paid more attention to Dr. Gold's lectures, I doubt I have notes on how he calculated the uncertainty of a chi-square fit.

I will definitely have to analyze how close using the average of the data as [math]\displaystyle{ \lambda }[/math] gets to the [math]\displaystyle{ \lambda }[/math] calculated by a chi-square fit, since as both you, Bradley, and the world has pointed out, [math]\displaystyle{ \lambda }[/math] is the average of a Poisson distro. It looks like the Poisson distribution has another way to fit it not based on chi-square but still based on maximum likelihood, from the looks of the wiki article.

Looks like I have plenty to write about. --Tomas A. Mondragon 18:50, 25 October 2007 (CDT)