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Raoul

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Raoul
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  • If you uncheck the intercept in the model then you should get a z-value for both groups, testing their mean agains 0.
  • Hi kassiopeiia, The moderators that you describe are categorical. A categorical variable is encoded with dummy variables. There are always one less dummy variables than the number of categories. Please consult a good book on regression analysis. I s…
  • Hi Priyesh99, Usually the SE can be obtained (or approximated) from the sample size (and an estimate of the effect size), or it can be inferred from a combination of an estimate and a test statistic. There are many good sources and text books on eff…
  • I'm assuming you mean you want to meta-estimate the product c' = a*b in the mediation X --a--> M --b--> Y. The problem of the SE of c' = a*b is that the analytical SE's are unknown, and that's why people usually use a bootstrap to find that (f…
  • There is currently no way to specify weights for the meta-analysis in JASP. Although perhaps it is possible to weigh the effect sizes and their standard errors by hand and import those weighted data into R. But I would suggest that it'll be easier t…
  • Metafor is capable of many methods. They are all listed in the method dropdown menu. You have to pick one of them. This implies that metafor cannot do a fixed- or a random- H&S meta-analysis, it can do a fixed, a random, or a H&S meta-analys…
  • Hi Fotini, The current version does not yet include rma.mv() unfortunately. Hopefully it will in a near future release when time permits. Yet, I highly recommend to simply use R and the metafor package to run this more sophisticated analysis (and p…
  • Hi Ravi, As a follow up to EJ: I have nothing to add It's true that most people mindlessly recommend random effects over fixed effects. A good discussion of this choice can be found in (Hedges & Vevea,1998). In summary it comes down to whether y…
  • I'm not exactly familiar with this particular method, but I think the title marked in the ellipse is simply a generic title that was not tailored to this particular method choice. The metafor-project's website gives a more complete description of wh…
  • Rick, Indeed it does. I don't know exactly how I² is calculated when REML is used. A good place to find more information is: http://www.metafor-project.org/doku.php Raoul
  • @rick_m Your formula is correct if you use the DerSimonian-Laird estimator (which is *not* the default). See the plot below. I have not checked wether the calculation of I² is correct for the other options, but I have checked whether it is the same …
  • Hi Michelle, Could it be that you don't convert the sampling variances (vi) into standard errors (SE) by taking a square root? Otherwise, do you have an example JASP file that illustrates the problem? Raoul
  • Hi Max, The meta-analysis module in the current version of Jasp does not yet allow for this. The next release probably will allow for what is sometimes called 'multivariate meta-analysis'. If you need to get to it right away, I recommend to have a l…
  • Not sure what you mean exactly by 'hierarchical regression', but the interaction between an dichotomous and a continuous variable in a meta-regression involves 4 parameters that have to be estimated (intercept, coefficients for the dichotomous and c…