HN user

EpiMath

75 karma
Posts0
Comments36
View on HN
No posts found.

I'm not very sure about the vinegar + steal wool part... that makes ferrous acetate pretty quickly, and what we want here is a ferro-gallate. I think there are ways of producing ferro-gallate inks without using sulfates, but historically ferrous sulfate was commonly used ( and leads to paper being eaten away over time )

Excellent comment. I'm one of those people who always thought: "I can't draw". Now I understand that for me it is a matter of practice. I started with Drawing on the Right Side of the Brain.

Is Math Real? 3 years ago

This book is not really addressing the more common "is math real" question of it being empirical or invented. For an interesting take on that question, see the 1st section of the 2nd part of Daniel Shanks' Solved and Unsolved Problems in Number Theory. He makes some interesting points about the old Pythagorean views

Is wine fake? 4 years ago

I've also been roasting coffee from Sweet Maria's for many years, and the thing that's useful is that I learned how Tom will describe flavors that I like. So, whether he calls it "hazelnut" or "almond" doesn't matter, but when he says "hazelnut" there is a flavor I enjoy that isn't there when he writes "almond"... and some other things like when he writes 'crowd pleasing" there is likely to be a lot of balance... over time the descriptions have become more and more useful to me!

good comment. This seems to come up more in number theory than in foundations/philosophy of mathematics, but I agree is has an important place. Not just triangles, but natural numbers having a fundamental place in reality ( e.g. integral numbers of dimensions, degrees of equations at the foundations of physics, etc., etc. Daniel Shanks has a list of about 60 of these "arguments" for Pythagorean interpretation of numbers )

There was a paper a few years ago in the American Mathematical Monthly ( sorry... can't remember the author, I think it was a Russian mathematician ) that gave some interesting heuristics for why this form is natural to consider, where the 1/30 comes from ( and considerations of a couple of alternatives to the "30" ), and the kind of intuition/thinking that Ramanujan may have used. When you only see the final form of the equation like this, it looks very mysterious and impossible that someone could find it ( and to be fair, there are other results from Ramanujan that are definitely in that class! ). Probably a google search could find the paper, it was delightful to read.

Agreed, and current estimates are more on the order of 4 to 5 per million. A high proportion of these cases are among people with a history of anaphylactic reactions to drugs, needle sticks or food/tree nuts ( many were already carrying their own epi pens! ) so it includes people who probably would skip an annual flu vaccine but of course do not want to skip this one. I'm not trying to suggest that the rate isn't higher than other vaccines, but it may not be as much higher as it first appeared. ( Also, to be fair, now that there is so much vigilance, it's possible that a number of pre-anaphylaxis are being caught early and treated with epi or benadryl before they could become full-blown anaphylaxis. So, this could make the rate appear lower. These things always need to be considered thoughtfully! )

As others have pointed out, the risk/benefit calculation here is extreme: a few bad reactions per million vs. a disease that has already killed more than 1000 people per million population in the US.

If you've got enough math background to follow it, Harold Edwards' Riemann's Zeta Function is a gem of a book and available inexpensively from Dover. There is an English translation of Riemann's paper at the end of the book. I spent a worthwhile few weeks of spare time working my way through the paper ( and a lot of pencil & paper to work "between" the steps in the paper -- math is not a spectator sport ) with a longish diversion diving into the gamma function along the way.

Yes, okay. There are implicit assumptions in scientific studies ( e.g.: there are no invisible elephants, or the study we are doing is actually related to the question we are investigating! ). Power calculations refer to the model and not to whether it is the correct model. To some extent we routinely worry about certain types of "hidden from observation" problems: we have zero-inflated poisson models, or we worry about what happens if there is a limited susceptible subpopulation ( that could deplete over time differentially depending on treatment, etc ). But it is not correct to suggest that if a study of whatever power does not find an effect, then a huge effect and no effect are equally plausible.

I have seen outrageous examples of "accepting the null hypothesis" many times, but many negative result studies have great value and even a single negative study can provide evidence against a very large effect.

This is why we report statistical power. It does in fact put probabalistic limits on the size of the elephant. In effect, we can make a statement like "at least 90% of studies like ours will detect an elephant larger than 20 microns if it is actually there on the table". It's not reasonable to interpret the results of a single study without consideration of power.

Agree Feller is excellent. I don't think it has much in the way of prerequisites and comes at probability from a solid "fundamental understanding" POV.

Volume 2 is more difficult but also very good.

Don't forget that you always read mathematics ( or probability theory ) with a pencil in hand. It's a participatory activity.

Project Euler 9 years ago

If you mean Hardy and Wright's Introduction to the Theory of Numbers, I agree it is excellent, but you can solve the great majority of the project Euler problems without going to quite that level. I particularly enjoyed Daniel Shank's Solved and Unsolved Problems in Number Theory but even that goes beyond what is necessary.