Johnny Felt
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jfeltphd.bsky.social
Johnny Felt
@jfeltphd.bsky.social
Quantitative methodologist interested in Bayesian and frequentist approaches to longitudinal data analysis, causal inference, and measurement. Assistant Research Professor in the Center for Healthy Aging at Penn State. UC Merced Quant Psych Alum.
I think the issue is that we can’t know if it’ll give the same results, in our specific use case, until after doing all that work, which also sucks.
October 9, 2025 at 2:08 AM
I remember the tabachnick and fidell book “experimental designs using ANOVA” that I used in my MA program being super helpful, but it’s been a while since I looked at it.
October 1, 2025 at 5:18 PM
I learned in grad school to not rely on p-curve analyses from Will shadish and Jack Vevea. I was surprised to see them used so frequently after I graduated, but I could never find a paper backing up what I was taught until now!
August 8, 2025 at 8:25 PM
Oh I see! Then I also agree lol
July 31, 2025 at 12:16 AM
Which is why the causal inference we work with is probabilistic and not deterministic
July 31, 2025 at 12:00 AM
I’m with @solomonkurz.bsky.social . Is this how the field is looking at causal inference? The causal inference class I took in grad school and the ones I teach focus on how we typically only have INUS conditions.
July 30, 2025 at 11:58 PM
All this! I just did a causal inference workshop at Penn State and I started off with “stats can’t save you here. Causal inference is a qualitative inference given the data collected and the design of your study.” It was very Shadish, Cook, and Campbell heavy with a dash of DAGs
July 23, 2025 at 6:56 PM
This book was so good! Have you read jonathan strange and mr norrell yet?
July 19, 2025 at 2:24 PM
The tabachnick and Fidell book, analyzing experiments using ANOVA. has a nice section on a priori contrast for one way and factorial ANOVAs. They even include a table at the end for different contrast based on the number of groups you have. Linda collins MOST book is a good one too
July 2, 2025 at 1:57 PM
If MCAR, I’ll just randomly impute 1s and 0s so I don’t lose power
June 23, 2025 at 6:07 PM
Oh absolutely. Unfortunately it means you’ll have to double check these errors in lme4 before determining if they are erroneous though
May 19, 2025 at 2:38 PM
Another thing to request, particularly when using lme4 or nlme in R, is the confidence intervals. If you just do a summary on the model object, you won’t actually know if your model has converged, particularly in the random effects. Asking for confint (in lme4) or intervals(in nlme) will check this
May 17, 2025 at 11:13 PM
As a Sacramento kings fan, I am a fan of anyone that is a thorn in the Lakers side. Go Celtics!
April 20, 2025 at 5:23 PM
Have you been telling participants to “git gud” in your studies?
April 8, 2025 at 10:08 PM
Wow, this is an impressive three to have in one talk!
April 8, 2025 at 10:05 PM
I once heard someone say that “they didn’t need to randomize because the data were all collected so close in time to each other”
March 24, 2025 at 11:47 AM
Definitely this paper. It is written so clearly without a lot (or any equations). It helped me also see that the whole DAGs framework also fits with the threats to validity and the Rubin’s causal framework
February 28, 2025 at 3:58 PM