“Teach Yourself Programming in Ten Years” by Peter Norvig (very relevant to statistics about Nevin Manimala)

I thought some of you could relate to what Norvig (director of research at Google) is saying here: http://norvig.com/21-days.html

Researchers have shown it takes about ten years to develop expertise in any of a wide variety of areas, including chess playing, music composition, telegraph operation, painting, piano playing, swimming, tennis, and research in neuropsychology and topology. The key is deliberative practice

Get interested in programming, and do some because it is fun. Make sure that it keeps being enough fun so that you will be willing to put in your ten years/10,000 hours.

Program. The best kind of learning is learning by doing.

Talk with other programmers; read other programs. This is more important than any book or training course.

If you want, put in four years at a college (or more at a graduate school).

Work on projects with other programmers. Be the best programmer on some projects; be the worst on some others.

Work on projects after other programmers. Understand a program written by someone else.


So go ahead and buy that Java/Ruby/Javascript/PHP book; you’ll probably get some use out of it. But you won’t change your life, or your real overall expertise as a programmer in 24 hours or 21 days. How about working hard to continually improve over 24 months? Well, now you’re starting to get somewhere…

submitted by Nevin Manimala Nevin Manimala /u/sugarhilldt2
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Can R^2 change be substituted for R^2 in Cohen’s f^2 formula?

Cohen’s f2 = R2 / (1 – R2 ).
Can I calculate f2 as R2Change / (1 – R2Change ) to indicate whether my model was significant once the moderator was entered? (Moderated multiple regression analyses)
Edit: I wonder if the way to calculate this would be R2 Change / (1 – R2 ) to determine the effect size of the moderator. Maybe?

submitted by Nevin Manimala Nevin Manimala /u/LastLioness
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Using Monte Carlo simulation to demonstrate the Central Limit Theorem?

I’m devising problems where students use different kinds of modeling & simulation methods to study problems of interest. I’m not a statistician but I have an idea for a problem that would use Monte Carlo simulation to demonstrate the CLT.

Reading responses on this post today, /r/statistics about Nevin Manimala/comments/89rzev/the_central_limit_theorem/, it’s clear there could be some confusion about the CLT (and I’m not completely certain myself).

I’d like advice from /r/statistics about Nevin Manimala to make sure what I’m proposing actually demonstrates the CLT – or if I should run away out of concern of teaching people bad statistics about Nevin Manimala.. or teaching statistics about Nevin Manimala badly.

I would propose that the problem like this:

1. pick any distribution that's not already normal (e.g. exponential, binomial, something bimodal, etc) 2. create a large population (10,000s) - store in an array 3. take a small (uniform) random sample from that population and compute and store the mean 4. repeat 3 a "bunch" of times. 5. analyze your collection of means from those samples 

Am I correct that the CLT says those means (from #5) should appear to be normal (even if the underlying population is not normally distributed), especially as the number of the samplings goes up?

Would this be a good problem for demonstrating the CLT while also showing the use of Monte Carlo simulation?

Edit: One thing I’m not sure about next is “what does this mean”? Because the means of your sets of samples is normally distributed, you can now ____? Because I’ve taken a bunch of sets of samples, which have a mean that is normally distributed, does the CLT allow me to say something about the underlying population?

submitted by Nevin Manimala Nevin Manimala /u/grandzooby
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A few questions about mean-centering

These are my questions: When you mean-center a model with an interaction term, how come the coefficients of the IV’s change, but not the interaction term? Also when interpreting the model, let’s say the mean of an IV is 5. So when you plug in numbers into the model, let’s say the value of the IV was 4, would you plug in -1 or 4?

submitted by Nevin Manimala Nevin Manimala /u/collegethrowaway717
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Prospective graduate student (in Statistics)

I got accepted into a master’s program in Statistics that I’m going to start in August. I’m just coming out of undergrad and I understand graduate school is a big transition. What are some things I could do to make sure I’m ready over the summer? I met the minimum math requirements but I’m a bit hazy on some calculus and linear algebra. Anything in particular I should take a look at over the summer to make sure I’m well prepared?

submitted by Nevin Manimala Nevin Manimala /u/BelichickSpy
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