Can’t get the high school math right on this…

I’m trying to get murders per 100,000 inhabitants per US state per race. I have UNODC murder rates for the US as a whole, African–Americans as percentage of total population (1790–2010) by U.S. state, and White American population as of 2000 and 2010 censuses and a year common to each of these tables. I figured it was state_race_rate = 100000*perpetrator_count/(state_population*race_percent) but the histograms of the states don’t spread out nearly as far as I supposed they would against the histograms of the countries. You can see my work on this notebook. What am I doing wrong? submitted by /u/dbabbitt [link] [comments]

What are open statistical problems in climate change science?

I’m getting a Ph.D. in mathematics and I’m basically studying mathematical statistics. The problems I work on have economics/finance workers as the primary audience. While I like these types of problems I see climate change as the most important issue our species faces, and I would like for my talents to help address this problem. So what are the statistical problems climate change scientists would like answered? Or what’s some good background reading on the statistics of climate science? Good books and review paper references appreciated. I may not do anything on this now while I’m still getting my Ph.D., but I could see myself looking into these problems after I get the Ph.D. submitted by /u/NTGuardian [link] [comments]

Best way to compare several cases to a null model

At the moment I am doing analysis in some data that is (currently) divided by number of individuals in a group. More or less like: Groups w/ two individuals: Value_1, Value_2, …, Value_N Groups w/ three individuals: Value_1, Value_2, …, Value_M In this case there were N groups of 2 individuals and M groups of 3 individuals. And so on until groups of about 300 individuals. Basically, I have different amount of data for each group size. I am trying to compare these experimental results with simulations I’ve ran as a null model. Currently, I run my simulation for each different group size then do a t-test for the means. However, I am left wondering: Is there any better/more interesting way to test how the experimental data differs from my null model/simulation instead of doing individual t-tests for each group size? Is there a way to aggregate all these tests into just one thing? submitted by /u/mechanical_fan [link] [comments]

one-sided log rank test

Hello everyone, Since the survdiff function of the survival package in R performs a two sided log rank test where the log rank statistic follows a chi2 distribution under the null hypothesis, is it okay to take the square root value of the test statistic (the sign depending on the difference between the observed and expected number of events in the chosen group) to perform a one sided log rank test? The square root statistic would then be compared against a standard normal distribution… Thanks for your input ! submitted by /u/OlivBad [link] [comments]

Sum of normally distributed samples

The formula for the expectation of a normal distributed function is N[mu,mean], where mu=0 and variance=1, as n goes to infinity. This is given by 1/n∑xi p->n->infinity E[X]=mu=0 but which part of the formula makes it go to zero. Is it the sum that cancels out, e.g. -inf+inf=0, or is it because of the divisor (n) is increasing? Now, if we decrease the interval [infinity, -1] and [1,infinity], what happens with the sum then for normally distributed samples (they could be in the interval [-inf,inf], but we do only study those that are [>-1 and

Getting a BS in computer science. Will it be possible to be admitted into an MS statistics program?

Title. Goal is to go into data science, or maybe even get a phd many years later on and become a professor. Or if things don’t work out use the BS in computer science as a backup degree. But there’s not much overlap between CS and statistics, so I’m wondering if grad programs will accept someone like me in the first place. submitted by /u/680links [link] [comments]

Are Statistics Graduate Programs Less Competitive Than Applied Mathematics Programs?

I’m thinking about both MS and PhD programs. EDIT: Would some one be willing to give me an honest to god evaluation of my app profile through a PM? I took the GRE yesterday and am starting applications now. submitted by /u/keepitsalty [link] [comments]

Simple Questions – November 16, 2018

This recurring thread will be for questions that might not warrant their own thread. We would like to see more conceptual-based questions posted in this thread, rather than “what is the answer to this problem?”. For example, here are some kinds of questions that we’d like to see in this thread: Can someone explain the concept of maпifolds to me? What are the applications of Represeпtation Theory? What’s a good starter book for Numerical Aпalysis? What can I do to prepare for college/grad school/getting a job? Including a brief description of your mathematical background and the context for your question can help others give you an appropriate answer. submitted by /u/AutoModerator [link] [comments]

Looking to do a Masters and most unis mention that Stats post-graduates are very high in demand. Is this true in your experience?

To also mention that im in Europe, so even better if you are a european and you can share your experience on the matter submitted by /u/Niklios [link] [comments]

Any suggested readings or tutorials on Functional Principal Component Analysis?

Messing around with the new JMP tools for Functional Principal Components. Have some projects already, but would love to find some good examples of discussions on the tool to get my juices flowing a bit further. Any suggestions? submitted by /u/Hellkyte [link] [comments]