Recent content by fed2

  1. fed2

    How common is it for researchers to omit a power calculation?

    oh i see. it can sort of be interpreted as 'science is hard if you can't explain much of the variation you are seeing'. Some medicines are very effective, for example many vaccines are >70% effective relative to placebo, at least in a lab. Condoms are also very effective, ive been told.
  2. fed2

    P value after Geisser-Greenhouse correction

    SAS GLM agrees with the above. Looks plausble to me given what I know about these adjustments, which is not much. Its actually not halving the p-value, in the sense that 'the p-value' assuming sphericity is labeled 'sphericity assumed'. Proc mixed gives the 0.008 as well. Well id say if 3...
  3. fed2

    P value after Geisser-Greenhouse correction

    Interesting. Do you have any other software to check against? If you send me data I will check against SAS when I get a chance. What prism are you using? What do the prism docs say?
  4. fed2

    How common is it for researchers to omit a power calculation?

    I don't know, seems like tail wagging the dog here. You know that a study is underpowered because you can 'easily construct a plausible scenario', then how do you know the plausible scenario holds? I am more familiar with the mantra hlsmith was reciting above, ie , I don't reckon its a...
  5. fed2

    Non-unique raters: ICC or Fleiss' kappa

    Maybe, but im still getting that stats tingly feeling. do you feel different or same as the attached, why or why not? do you already sum the scores on the questionaire?
  6. fed2

    Artifact in plotting CDF with oil and gas data?

    i guess the question is what does it mean for the relationship to be 'very apparent'. Some of it may be an artifact of reduced sample size in some tertiles, for example you don't gots alot of blue dots on yer upper tertile plot? You may want to try log-rank test or other formal CDF comparison...
  7. fed2

    How common is it for researchers to omit a power calculation?

    how do you know if it is underpowered?
  8. fed2

    Non-unique raters: ICC or Fleiss' kappa

    Are the many retirement homes? ie what is being rated, the (assumed common) service of a given retirement home, or the experience per old (senior citizen?) person? Are you actually interested in qualifying the raters/rating system, or is it just the agreement between the two raters you care...
  9. fed2

    How common is it for researchers to omit a power calculation?

    Its very common, in fact I prefer it. Periodically someone will write something about how not reporting this is very important to 'quality', then people do it for a while, then stop. This cycle continues with no observable effect on the science.
  10. fed2

    Odds Ratio question

    thats essentially right. For the analysis of matched data you would have to adjust for the matching variables in one fashion or another, these include: 1) Chochran mantel hantzel - adjust for the matched groups. 2) McNemars test, conditional logits (what was used in your paper), or related
  11. fed2

    Odds Ratio question

    The answer is essentially no, barring some trickery. This study may have some trickery though, because of the way things were done its not strictly a case-control in the usual sense. By generally, the crude OR (by which I mean the population OR that would be obtained without matching) would...
  12. fed2

    WANTED: Rational Coronavirus Analysis

    Well don't look at me, i just *accidentally* stumbled in here as well. But since we were all spotted at the scene of the crime, I think that honor among thieves dictates that we all go our separate ways and not speak of it again.
  13. fed2

    Odds Ratio question

    I got same as you, but I think mystery is in ' We used conditional logistic regression', so basically it is giving the 'matched odds ratio' associated with McNemar's test, https://horvath.genetics.ucla.edu/html/Class100B/Lecture2McNemarbasedonlc19.pdf. But I think it may be a little more...
  14. fed2

    WANTED: Rational Coronavirus Analysis

    yeah i dont know, i sholdn't encourage you with this but its more entertaining than the usual normal curves fair. I just wonder how some of these people get to such high places in these government agencies without knowing how to kiss up better. If el jefe says the trend is down, then draw a...
  15. fed2

    Confidence Intervals for Incidence rate

    probably be poisson in this case, i assume because it is per 100,000, that is there is probably loss to follow up.