Recent content by Signifier

Again thank you both, this has given me a lot to think about and learn.

Thank you both. This was really useful. Stephen Tashi: what you've described seems more complicated than what I have done, so I want to check my understanding. For what I'm interested in (is there a significant difference in the % of mutants and % of non-mutants who like cheese?), can't I just...

Hi all, I have no experience with multivariate statistics but I'm trying to figure out a type of problem that seems like it should be easy, but I don't know where to begin. I ran into the problem in my research, and I don't have a strong statistics background. I'll try to explain it with an...

Hm... a very interesting result. I have been calculating interaction parameters for the rare gas atoms. Following Pahl, Calvo, Kocˇi, and Schwerdtfeger (Angew. Chem. Int. Ed. 2008, 47, 8207 –8210), I've calculated the de Boer parameter for the different RG atoms, getting for instance 0.027 for...

Hi, I was wondering how to calculate a rough estimate of the temperature at which quantum effects begin to become important for a gas of interacting particles. Let's say the particles interact via a spherically symmetric potential with an equilibrium distance R and a well-depth E (such as the...

I can't remember if I already posted this and lost track. Sorry if I did. I'm not sure if this question is "not meant for this forum" but I don't know where else to ask, or where my last post went. I was looking for recommendations for books and or webpages useful for graduates doing...

Get a PhD in philosophy from Brown. And start running. Get addicted to runner's high.

Hi, I was wondering if anyone could recommend books useful for learning how to "do research," to put it bluntly. Almost all the books I could find at my school's wimpy liberal arts library seem concerned with doing research to write a research paper for a class, not on actually doing research on...

The analytical solution for the wavefunction of a hydrogenic electron with quantum numbers n, l and m has a spherical harmonic part that involves theta and phi (in spherical coordinates). I was looking in Griffiths, and the spherical harmonics part only has phi as exp(i m phi) where i is the...

OK, that's a good assumption in my case. It would mean that the uncertainty in the slope is equal to the uncertainty in y, right? Unfortunately I don't have Excel and I'm doing this all by hand, heh. How do I calculate the standard errors for both parameters by hand?

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 strongly positively correlated. I do a linear regression and get an equation for a line of best...

In all of the physics books I have, the story is Millikan, in measuring (calculating) the charge found on tiny oil drops, "found them all to be integer multiples of a single, fundamental unit", the electron charge -e. The question I have is, HOW did he show them to all be multiples of a...

Hello, I am beginning rudimentary work on a senior thesis. I am getting tired of hassling with Word to format all my formulas and proofs, and I thought about using proTeXt but I don't want to download 540 mb. My friend told me (a few years ago!) about a program called "Tech," but he might have...

Hello, the work I am doing now requires numerical solution of several reaction-diffusion equations such as the standard advection diffusion equation (ADE) or IE Fisher's equation. So far I have been using the only method I am familiar with, the simplest one I believe: to express the time...

Kummer: N = 1 along y = 0 means: N(x, 0) = 1 (all of the points along the line at the top of the square, at y = 0, have unit concentration). I will now consider your response... thank you.