# Search results

1. ### probability of 3 close family members all having an eye disease

Well, right, of course your wife would be independent of you, but the point is who are you asking about? Your wife, her brother and you, for example is different from you your son and your daughter. (Since you are trying to generalize the question.)
2. ### Regression analysis across multiple data sets

I don't have anything to disclose, this is just a free, good, lower-level explanation and video: https://thecraftofstatisticalanalysis.com/random-intercept-random-slope-models then watch this https://thecraftofstatisticalanalysis.com/fixed-random-factors
3. ### Regression analysis across multiple data sets

might want to consider first dimension reduction or penalized regression since you have so many potential predictors. I would start with theory (i.e. higher free cash flow to equity is theoretically associated with stock price being higher, all else constant, and FCF to the firm is associated...
4. ### Regression analysis across multiple data sets

You'll want to look into a mixed model, then. Treat a company as a random effect. What is the outcome of interest?
5. ### probability of 3 close family members all having an eye disease

I think @Dason is making the point that the 1/10,000 might be a marginal probability (think of disease prevalence in the general population or lifetime incidence or something to that effect), but these are not independent cases because family members are genetically linked and the probability of...
6. ### how to calculate mean follow up

I'll try to grease the wheels: 1) the formula I gave is just another way of writing your formula. 2) Where are you getting the formula that you're suggesting? The point is to encourage some independent search and discovery. Did the formula come from a website, a book? Trying to use the teach a...
7. ### how to calculate mean follow up

I'm not saying it's wrong, but I'm asking why are you using that formula? Why not (.2)*(40 + 38 +37) + (.4)*(30) ? (Trying to encourage some learning, metacognition.) If that is the right formula, do you think the median would be more appropriate here? What about the mode?
8. ### how to calculate mean follow up

What is the formula for arithmetic average?
9. ### rating the accuracy of predictions

How are the exam results given? Are they points out of 100 or letter grades? Does every student have only a single score? are these exam results for a single test, a single course? What is the typical class size? What is meant by weight/rank predictions (simply whose prediction was the best by...
10. ### What test to report?

Let me clarify: the Mann-Whitney test is equivalent to the Wilcoxon rank sum test-- I agree with you-- no problem. The problem in the book is that for dependent samples they only say "Wilcoxon" which is poor form on their part because there are two "Wilcoxon" tests: the Wilcoxon rank sum (same...
11. ### What test to report?

I know I'm not directly helping with the references, but I've read some good discussions and seen simulations that show that the tendency for the sampling distribution to be approximately normal (at various sample sizes) does depend on the degree of nonnormality in the underlying distribution of...
12. ### What test to report?

You already received your answers: just discarding outliers to "not influence the outcome" is incredibly wrong; there's a problem in statistical education these days, mainly because many people are allowed to teach without a good background. In reference to "and an extremely small effect size...
13. ### What test to report?

The teacher’s advice and that textbook are the equivalent of toilet paper. No offense to you.
14. ### Likert scores - how to deal with them?

This might be useful background to have https://files.osf.io/v1/resources/3tkz4/providers/osfstorage/5a00c503b83f6902641e68f3?action=download&version=3&direct I think @spunky or @Jake shared this earlier?
15. ### Paired or Unpaired?

Yes, paired t test would be a good idea. Do you have other variables like age, gender, or comorbidities? However, the reviewer is wrong in that data are "non parameteric” or “parametric”: these terms refer to larger groups of statistical tests or estimation procedures. It is incorrect to call...
16. ### Paired or Unpaired?

Other important issue that people commonly misunderstand: the Mann-Whitney U test (wilcoxon rank sum) and the wilcoxon signed rank test (paired samples) do not compare medians, in general. Only under much more restrictive assumptions could this be true, and then I believe you have enough...
17. ### Interaction

What makes you think running a logistic regression doesn’t give you a simple answer?
18. ### Performance evaluation

I’ll try rephrasing what the others have correctly said: statistical tests are for making inferences (drawing conclusions) about something unknown on the basis of a sample that is supposed to represent the unknown. The statistical test incorporates uncertainty from the sample to help you say...
19. ### Basic Stats - Emoji Assessment

Yes. That is difference because it is a ratio-scaled measurement.
20. ### HYPOTHESIS TESTING (ALPHA)

1) A type I error isn't a false positive, necessarily. If you look at it from the case that the null is true then rejecting the null may be viewed as a false positive, but the alternative is another perspective in that now that the null is rejected, is it a correct rejection (i.e. looking at all...