we conducted a replication study, and I have a question on the priors. For the data analysis in both studies, we used Bayesian regression analyses. Is there a manual on how to adapt the prior settings for study 2 (i.e., the replication study) based on the posteriors in study1? Or would you rather use a "study-variable" (factor levels: study 1, study2) as an additional predictor, (how) would you adapt the prior settings in this case?

Thank you for your help :)

Best,

Cathy

]]>I'm new to JASP and I'm currently experimenting with the functions. I just watched the YouTube video for the logistic regression but that still didn't help to answer my question. That's why I'm now asking you for help. I am wondering if you can do an assumption check for a logistic regression in JASP?

Thanks for your help!

P.S: Sorry, I propably posted it in the wrong category but can't delete it anymore. I wasn't aware I was chosing a category to post it in.

]]>But when making a table of Bayesian correlations in JASP and opting to "flag supporting correlations", it does so based on Bayes Factor thresholds of 10, 30, 100 (ie, missing out the 3).

Is that an oversight in the JASP code which flags supported correlations? Based on the papers it seems like the best thing to do in the short term is for me to manually edit the exported JASP tables to add the threshold at 3, so the table legend looks something like

"* BF10 > 3, ** BF10 > 10, *** BF10 > 30, **** BF10 > 100"

Thanks. Ben

Reference

Doorn, J., van den Bergh, D., Böhm, U., Dablander, F., Derks, K., Draws, T., et al. (2020). The JASP guidelines for conducting and reporting a Bayesian analysis. *Psychonomic Bulletin & Review*, *66*(2), 1–14. http://doi.org/10.3758/s13423-020-01798-5

Wagenmakers, E.-J., Love, J., Marsman, M., Jamil, T., Ly, A., Verhagen, J., et al. (2018). Bayesian inference for psychology. Part II: Example applications with JASP. *Psychonomic Bulletin & Review*, *25*(1), 1–19. http://doi.org/10.3758/s13423-017-1323-7

I've been experimenting with setting seeds for Bayesian analyses. I've set my seed in one data file, and then created another JASP file with the very same data. I re-ran the analyses with the very same seed and got different results - some of my Bayes factors have changed by as much as six! Is this something to worry about?

Kind regards,

Anna

]]>I'm new on this forum but I use JASP a lot, both for research and teaching so I think I'll like it here !

I'm using cluster analysis (K-means) for the first time on two variables. I use JASP to draw the plot, and the output is this :

Now, one of my colleague says that "you need to make the dimensions apparent".

Is this true ? Can I and should I find out which dimension is on Y and X and make them appear (for a scientific paper) ? I somehow thought that because of the unsupervised nature of K-means clustering I'm not allowed to use labels. But if there are only 2 variables, I guess you can somehow them on a 2D graph.

I'm looking for your help on this question, and notably how to perform it on JASP if I have to make the label appear. Thank you very much and have a great day !

]]>I watn to run my first SEM, and I have a model with latent variables and a mediation.

This is how I done for one independent variable (E_1)

M =~ M1 +M2 +M3 +M4+M5+M6

E_1 =~ QE1+QE2+QE3+QE4+QE5+QE6+QE7+QE8

T_2 =~ QT1+QT2+QT3+QT4+QT5

# regression

M ~ alpha * E_1

VD~ beta*M + direct* E_1

indirect :=alpha*beta

total :=indirect + direct

proportion := indirect/total

But how can I do for the add the other one (T_2)?

Thanks for you help!

]]>I want to use multiple Bayesian Mann-Whitney-U tests to compare two experimental groups before the experiment (age and stuff like this, 11 comparisons in total).

How do I correct for multiple comparisons? The test allows me to adjust the priors, however, I have no idea how I should to this.

Has anyone any tips or literature recommendations?

Cheers,

Max

]]>I was just wondering if there was a way to get beta values for the bayes regression output? I believe that the mean value in the posterior summary table is B, but is there a way to find beta?

Thanks

Emily

]]>hope you can help me with my problem. I have performed a subgroup analysis in the course of my meta-analysis. So I wanted to ask you how I can calculate the heterogeneity (I^2 = xy %) between the subgroups?

I would be very grateful if you could help me,

Nik

]]>Also, with t-tests... SPSS (and PSPP) let you pick two categories from any category variable... will JASP ever do the same, instead of insisting on a dichot. variable?

I'm planning to use JASP for teaching because SPSS and PSPP give too many install headaches (and they say JASP is much easier to use, so they can focus on why they're doing what they're doing, instead of how to do it).

]]>I will start by saying that I am novice in Bayesian statistics, so I am really sorry if I mixed up some notion. I’m currently doing a research on the effect of heat on some bone microstructure. I want to test if there is any difference on the size of structure when exposed to heat. I have 45 bone, and each of these 45 bones has N=120 non-heated microstructure and N=120 heated microstructure, approximately. I wanted to do a Bayesian Mann-Whitney U test (in JASP) for non-heated structure vs heated structure of my 45 bones and for 5 variables (area, diameter, circularity, etc.), but I’m concerned about the multiplicity of tests and how to handle it.

In what I’ve seen so far, a correction can be applied by changing prior odds and then multiplying those with BF10 to get corrected posterior odd. My first question is: How important are the posterior odds in the interpretation of a Bayesian Mann-Whitney U test, since they are not reported in JASP for individual test (only with a post-hoc ANOVA) and for what I understand, BF are not concerned with the correction. With that many tests, I will certainly get a very important correction that will favor the null hypothesis. Are they any limits to the correction?

I choose to test each bone separately because bone microstructure is really variable across individuals and bone type. My goal by doing so many tests is to see if there is a global tendency and I’m worried that I would lose all evidence of an effect if I applied a correction. My argument for not doing a correction is : with that many tests, even if I have some false positive, my goal is to see the global tendency and those would not matter as much as if I would rely on each individual test alone to answer my question. Does that make any sense? I’m kind of lost here and any help would be very much appreciated.

Thanks a lot

Cheers

Fred

]]>I recently read a paper (Pfister, 2021) about the variability of Bayes factors and notably the fact that repeating a Bayesian ANOVA on the same dataset resuts in dramatical changes in Bayes factors. The author of the paper suggested to repeat the analysis a large amount of time and to report the trimmed mean of the Bayes factors. I would like to know whether it is possible to do that in JASP. I saw that there is Repeatability option in the Additionnal Options of the Bayesian ANOVA module where one can specify a seed. However, I am not sure how to use it and I feel that it is not really what I am looking for. I have no doubt that it is possible to use R to deal with this question but I am not familiar enough with R to do so by myself. Can someone help me with that please? Thank you very much in advance.

Best regards

Nico

]]>Thanks,

Philip

]]>I need to run several statistical analyses on JAPS with ordinal variables. In my SPSS file, they are recognized as ordinal. Usually when I open JASP, then the variables appears with the same types (scale, ordinal, etc.) than on SPSS. But it's not the case here (see pictures attached - all my variables are recognized as scales so I can't run my analyses) and I have no idea why - that's the first time I have this problem.

- I have tried on another computer and from the same SPSS file, my variables are correctly recognized as ordinal - problem is that I need to run a big model with Bayesian stats and that computer is not powerful enough
- I have already reinstalled JASP and tried different versions, the problem is always the same, that is, all my variables are recognized as scales in JASP.

Would someone have a solution?

Thank you!

Emilie

I have a question regarding linear regression in JASP. Our data require weighting so I chose the WLS option but I am not sure which variable must be entered here and could not find any comment on this in the help function or online. I tried to enter 1/SEM as well as 1/SEM² but the values were not within the required intervall. Entering SEM works - but is this correct? Does the WLS weight option calculate the reciprocal square of SEM itself?

Many thanks for your help!

Lone

]]>is there a possibility in JASP to get a measure of effect size when running a non-parametric ANOVA, thus a Kruskal-Wallis test (without having to calculate it manually)?

]]>I am hoping someone here can help me. I have generated the below funnel plot using JASP and checked the 'rank test for funnel plot asymmetry' box to estimate a p value for asymmetry. However, as you can see, the p value is 1.000 - which does not look correct when compared to the visual asymmetry in the funnel plot?

Is anyone else having this issue? Any help would be appreciated! Thank you

I analyzed the andy field’s beer goggles data set which is the effect of amount of alcohol consumed and sex on attractiveness of partner using Bayesian two-way anova. The model comparisons table below shows there is very large evidence for the interaction between alcohol and sex on attractiveness of partner.

Then, I tried to determine the simple effects of sex within each level of alcohol on attractiveness of partner using Bayesian independent t test. The table below shows that there is very large evidence for the alternative hypothesis at four beers.

I would like to know if there is a need to correct for multiplicity in the follow-up Bayesian independent samples t test. And if there is a need, how to correct for multiplicity.

Thanks and cheers

narcilili

]]>I am a student from the University of Tours (France) and I am currently doing my MA thesis on the longitudinal predictors of spelling performance from kindergarten until first grade of primary school. My data being abnormal, I would like to use Spearman's Rho correlations to analyse different variables I am looking at. Notably, I would like to know how to use partial correlations using Spearman's Rho. I saw an option on JASP called "Condition on" which allows to implement partial correlations. Is this the right operation? Are there any specific requirements, regarding the type of data or variables, to use this option ?

Thank you!

Sofia

]]>Correct analysis for (I assume GLM) & inputting data correctly as Jasp keeps returning unable to compute & remove factors? Many Thanks if you can HELP!!

]]>I'm currently doing an EFA and would like to add the Velicer MAP Test to the list. However, it doesn't seem to be available on JASP - did I miss something?

Thanks for your help!

]]>As being an old SPSS user I am not use to using files with CSV format. When I am inside JASP and I want to edit data using "data synchronization" by double clicking. My file is displayed as CSV but with very strange columns (se below) making it difficult to edit data. What must I do to get my CSV file to look "normal" like in the JASP tutorials ?

Thanks for replying π

]]>Jasp 0.14.1

I don't understand why some values are shown (randomly ?) wrong in my correlation matrix. Updated Jasp and reopened file - still does not work correct. How can I fix this?

student needs it to work for an assessment today.

any ideas?

]]>I'm conducting a mediation analysis (with 3 predictor, 1 mediator and 2 outcome variables), and I'm interested in getting the measure/s of "the goodness of fit" so I could compare models.

My professor mentioned that I could compare them by checking the "chi square for nested models" (If I understood him correctly), but I can't seem find that option in mediation analysis. Since I'm quite inexperienced, I'm interested about:

- How can I obtain the relevant measures?
- Which measures should be included and consulted as "the goodness of fit" parameters in that analysis/procedure, and;
- How do I report them?

Any information and suggestion would be highly appreciated.

Thanks in advance!

]]>I tested memory between 2 independent groups and will like to control for a covariate (degree of presence felt in VR). May I know what frequentist test should I run for this and what is its Bayesian equivalent?

Thanks a lot!

]]>I'm quite new to JASP. I want to run a mixed factor ANOVA with my data, but the raw values are not always normally distributed. I have multiple columns for my dependent variable at each measured parameters (and so they are not always normally distributed).

Is there a method in JASP to plot the unstandardised residuals for a given data-set to check whether the residuals are normally distributed (so that I can meet the ANOVA assumption)? I can't seem to find this in the manual or in any of the menus.

Thanks in advance.

S

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