# Search results

1. ### How to deal with outliers in stock returns? OLS regression January effect

I think your post actually makes the argument to leave the outlier as is because it does represent reality and you have no hope to properly understand or model the process if you take out outliers because they are "rare" (which is a loose definition for an outlier).
2. ### How to deal with outliers in stock returns? OLS regression January effect

I would not do anything. Outliers are expected and as long as this value is truly from the population of interest, it is OK; you should not remove outliers because they make things look different than you want. The idea is to accurately represent a phenomenon which may include a lot of typical...

4. ### Moving away from p-values

Let's clarify: your post claimed that "...while in Statistics "significant" means probably true (not due to chance)...When statisticians say a result is "highly significant" they mean it is very probably true." None of that is true. Then you also claim you [don't assume Ho is true when...
5. ### Moving away from p-values

This just isn't true. A very low p-value does not mean very probably true. This is part of the huge misunderstanding by (often) nonstatisticians. A p-value is calculated under the assumption that the null hypothesis is true. P-values do not quantify the probability of "truth" for any "result" or...
6. ### Clinical data sets and R scripts

A little confusing. Were you given a data set to work on as a homework/class project and an answer key exists somewhere, or are you conducting research? If the latter, your statement is puzzling that you know how to use R but want someone to provide the script because you would create that yourself.
7. ### Long live SAS

o_O Please feel free to use a quotation to show where I said that (or used foul language...or indicated that I don't have an open mind to those who know much more than I do). Otherwise, let's move along.
8. ### Long live SAS

Reading comprehension... where is my foul language? Don't forget that your post said, "SAS is for people who completely depend on somebody else for statistical / econometric advice." This is not the same as the slight pivot you tried in reply when you change it to, "...statisticians who used SAS...
9. ### Long live SAS

Did you get your PhD yesterday? Even people who got the PhDs in stats (that I know) in the early 2000's maybe up to 2015 even usually have a good working knowledge of SAS, just as you get more recent they have more and more R knowledge as well. The statisticians I know who were in school in the...
10. ### Corona hints

There were some autopsies in China, if I recall, where they saw some fibrosis, but the question is did this exist prior to infection or as a result of huge inflammatory process in the lungs in an intubated ICU patient over weeks. People with underlying lung disease will be more susceptible to a...
11. ### Multivariate regression versus multivariable regression

If you mean a single outcome (i.e. does the person bleed after surgery (Y/N)) as a function of 2 or more predictor variables, then you want a multivariable regression. If you have multiple outcomes that are being modeled simultaneously then you would want a multivariate regression. The latter...
12. ### Mean of the residuals in Simple Linear Regression *Beginner Alert*

And mine too, but generally the idea of plotting residuals vs x is to help see if you're misspecified!
13. ### Mean of the residuals in Simple Linear Regression *Beginner Alert*

Cause that's how the line of best fit is defined (partially), yaknow?
14. ### Mean of the residuals in Simple Linear Regression *Beginner Alert*

The nonlinearity could imply the mean error is not 0. True model: Y= B0 +B1X + B2X^2 Fit: yhat= b0 + b1x then Y-yhat = residual implies E[(B0 +B1X + B2X^2)-(b0 + b1x)] = E[B2X^2] not equal to zero for B2 and X not zero... so the average error would be B2X^2... this could show as curvature in...
15. ### Book/Website Recommendation

I will clarify that none of these suggestions are graduate-level. I think with your math background you can handle the probability book given. Mathematics is challenging. Statistics and probability are also hard subjects. Despite what you may see done, there is no quick fix for statistics. I...
16. ### Book/Website Recommendation

Agreed-- if you meant [calculus, linear algebra, geometry/trig, and some proofwork] as "math background" you definitely need the undergrad probability (and hopefully some mathematical statistics like Hogg and Craig or Wackerly/Mendenhall (at least) to get the most of ISL by Hastie et al. which...
17. ### Book/Website Recommendation

It always makes me chuckle when people suggest running before someone knows how to walk... try starting with Blitzstein's Introduction to Probability found here. Literally a free course and text book to give you a decent undergraduate background in some basic elements needed to adequately...
18. ### Cherry picking?

Unless they had pre-specified in a manner you can verify, there isn't an obvious reason to group A and B or whatever they did. @Karabiner is likely on the money they were just digging until they hit a rock to paint and call gold.
19. ### Corona hints

Does anyone have the original post but actually from Stanford? I've seen this a lot and there is a lot of controversy over this supposed "note from a Stanford guy's desk"-- some of it lacks evidence and some of it sounds plain silly. I think if Stanford or some other institution published this...
20. ### Rep and Seq

Thanks! Times parameter worked as you suggested.