Bayesian R-INLA?

Hi everyone, ​ I’m an MSc student studying ecology and currently working on my thesis. I need to do a patio-temporal analysis and the Bayesian Hierarchical Model R-INLA (r-inla.org) seems like it could be quite interesting. HOWEVER, I have minimal to zero statistical experience and am struggling quite a bit with understanding. ​ So I guess a couple questions: Has anyone ever used R-INLA and has advice for learning it as a beginner? Does anyone have any alternatives they think might be interesting for a spatio-temporal analysis? ​ If you would like more info on my thesis, feel free to DM me. Any help/advice/comments whatsoever would be immensely appreciated. submitted by /u/rainbowredwood [link] [comments]

Using PSPP and exact tests

Hi All, I have posted before about my current issue, but it was recommended by a stats professor at my university that instead of using a Chi Square test I should attempt an exact test because my sampled groups’ responses were so low. ​ I created a 10 question survey and then each question had a ranking answer of 1-5 with 1 being strongly disagree and 5 being strongly agree. The main variable is the students major which they chose from a list in the survey. SO now I am attempting to see if there was a significant difference in the way one major answered versus another major. ​ I am using PSPP and it was recommended I use a Kruskal-Wallis test…However that did not seem to work. I got a bunch fo NaNs and nothing pulling individual majors results. I have a screenshot of what I got and my raw data if it is of any interest to anyone. Any suggestions are appreciated! submitted by /u/tigerjust0001 [link] [comments]

Research Papers involving 2 Way ANOVA

Hi Folks at r/statistics, I’m currently attending a class that seeks to introduce statistical techniques. I’m particularly interested in the application of a 2 Way ANOVA. I would like to ask if anyone could provide some links to research papers that includes 2 Way ANOVA in their methodology (or any other statistical techniques is fine too). It would be preferable if the research paper would include parts such as; Breaking down the problem, Hypothesis testing with 2 Way ANOVA along with other further testing and conclusion.My apologies with this is the incorrect subreddit to approach. It would be highly appreciated if I could be direct to the proper subreddit for my request. submitted by /u/CeeZack [link] [comments]

Value at Risk calculation, without portfolio value. Are my calculations correct?

Hi! I’m doing a VaR calculation and just wondering if my numbers are correct. This calculation is without a portfolio value, so just the percentages of losses to be expected at a 95 % confidence level. ​ My = 1,12 Critical value for n>1000 = 1.645 Sigma = 0,44 ​ Based on these number, I’ve used the formula: Var= -X + σ*tα , IE: -1,12 + 0,44*1,645 = -0.3962. Based on my numbers, I will not lose more than 39,62 % of my portfolio in the 5 % worst of cases, or is it 1-0,3962 = 0,6038 = 60,38 %? submitted by /u/frysinatoren [link] [comments]

Leonhard Euler was the most prolific mathematician of all time. He wrote more than 500 books and papers during his lifetime — about 800 pages per year — with 400 further publications appearing posthumously. His collected works and correspondence are still not completely published

Most simple way to multiply 6 from the numbers 1 – 1000?

Heyo, I’m working on a leveling system with my Discord bot and I can’t quite think about how I would multiply 6 times 1 – 1000. I’m trying to get those numbers so people know the required experience to get to each next level.

How I have my system right now is each message sent gives 1 exp on normal rates and 2 on double. It takes 6 times the users current level to level up.

Thank you for your assistance.

submitted by /u/Basheas
[link] [comments]

A practical question from a rower

Hello Reddit mathematics community!

I’d like to pose a question – a practical one without an obvious or known answer, so far as I’m concerned, which I believe makes it permissible per the guidelines. This comes from my experience as a rower, and it revolves around a little thing we do called “matrixing,” which is essentially an on-the-water attempt to determine which rowers are faster and which are slower.

How it works, as we currently do it:

  • Every rower has a personal score, which starts at 0. You want this to be as low as possible by the end.
  • Each race consists of two 4+ boats (sweeping fours) racing side by side.
  • The difference in time to the finish of a 1 kilometer race between the two boats is measured.
  • Every rower in the losing boat has this time added onto their score. The winning boat’s rowers scores are left unchanged.
  • The rowers are shuffled around, and the process is repeated a total of six times.
  • The two ports and two starboards with the lowest scores ascend to the higher boat or the next round of matrixing.

Things to note:

  • Because the rowers are sweeping (one big oar) as opposed to sculling (two small oars), each rower will be acclimated to one side (port or starboard) and cannot switch sides. Each four consists of two starboards and two ports.
  • Fours are the only feasible boat to do matrixing in. Smaller boats (i.e. pairs) are not only more dissimilar in terms of boat-feel from the eight, they require much more practice before a new lineup can row effectively.
  • More than six races is infeasible within a standard-length practice (and given a rower’s stamina). Racing on multiple days is perfectly possible but differences in conditions mean that results are not necessarily comparable. This somewhat precludes a systems-of-equations approach, so far as I’m aware.
  • The rowing machine is an imperfect proxy for speed on the water, but a proxy nevertheless. A rower’s speed on the water can be projected with a very wide margin of error from on-land scores. I believe the r2 between the two is known, but I don’t have it on me.
  • Determining precise relative speed is not as important as ensuring that the top 2 rowers on each side are truly the top 2.

The question is: Does a better system for matrixing exist?

Feel free to let me know if you need clarification, specification, or anything else at all.

submitted by /u/judestiel
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Stack-exchange devoted to research problems, the suggested approaches and updates

Hi, I made a proposal to create an SE for math research problems: https://area51.stackexchange.com/proposals/122357/open-research-problems-in-math

To get it through phase one we will need up to 60 follows. I posted it on MO and got 4 follows from there. I would greatly appreciate if you can click on the above link and then click on “Follow” for the above proposal. You don’t need to do anything else. I will do the bulk of the work in creating.

submitted by /u/MAT337team
[link] [comments]