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Andrew Bell

@andrewjdbell.bsky.social

Senior Lecturer in Quantitative Social Sciences, University of Sheffield. Multilevel models, age period cohort, Intersectionality, etc https://linktr.ee/andrewjdbell

1,144 Followers  |  266 Following  |  3 Posts  |  Joined: 10.10.2023  |  2.05

Latest posts by andrewjdbell.bsky.social on Bluesky

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Now officially out with nice formatting and all πŸ₯³ "Thinking clearly about age, period, and cohort effects" -- a gentle introduction to the age-period-cohort problem and how to "solve" it through various types of assumptions.

journals.sagepub.com/doi/10.1177/...

06.06.2025 07:37 β€” πŸ‘ 277    πŸ” 70    πŸ’¬ 12    πŸ“Œ 6
A promotional graphic for the Research Methods Rendezvous, which takes place online on 10 September and 29 October 2025.

A promotional graphic for the Research Methods Rendezvous, which takes place online on 10 September and 29 October 2025.

NCRM has opened applications to participate in the Research Methods Rendezvous!

This free event will explore the process of turning early-stage ideas into #research projects.

#RMR2025 takes place online on 10 September and 29 October 2025.

Apply: www.ncrm.ac.uk/training/RMR...

05.06.2025 09:02 β€” πŸ‘ 13    πŸ” 18    πŸ’¬ 0    πŸ“Œ 2

Thanks to everybody who chimed in!

I arrived at the conclusion that (1) there's a lot of interesting stuff about interactions and (2) the figure I was looking for does not exist.

So, I made it myself! Here's a simple illustration of how to control for confounding in interactions:>

11.05.2025 05:34 β€” πŸ‘ 1135    πŸ” 275    πŸ’¬ 69    πŸ“Œ 18

Our research on the effects that PIP changes could have on local economies, written by authors @nataliecbennett.bsky.social @profbambra.bsky.social & @lukemunford.bsky.social, was featured on the @itvpeston.bsky.social programme last night - you can watch the episode on catch up

22.05.2025 08:46 β€” πŸ‘ 5    πŸ” 8    πŸ’¬ 0    πŸ“Œ 0
Jan Vanhove :: Blog - Collinearity isn’t a disease that needs curing

Another q for the stats people!
People worry about collinearity (cf blog post below).

Consider a scenario in which the collinear predictors are just controls to account for confounding.
Including both of them doesn't impair the precision with which the effect of interest is estimated, does it?

29.04.2025 12:26 β€” πŸ‘ 90    πŸ” 21    πŸ’¬ 14    πŸ“Œ 6
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Multilevel Models: Practical Applications

Curious about multilevel modelling but not sure where to start?

Learn to recognise, build & interpret multilevel models using MLwiN or R, through real-world examples & hands-on practice.

Find out more: bit.ly/3Yj5I4f

#ESS2025

11.04.2025 13:37 β€” πŸ‘ 2    πŸ” 3    πŸ’¬ 0    πŸ“Œ 0
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Still time to apply for this RA post- developing and applying the intersectional MAIHDA approach with @clarerevans.bsky.social and others. If you're a quantitative social scientist with an interest in quantitative methods and methods development, please apply! DMs open www.jobs.ac.uk/job/DMR190/r...

29.04.2025 08:50 β€” πŸ‘ 2    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0
Text reads: "An introduction to multilevel modelling for intersectionality research: the MAIHDA Approach. 19th June 2025. Instructors: Prof George Leckie and Dr Andrew Bell.

There are logos for Centre for multilevel modelling, NCRM, University of Sheffield, and UKRI

Text reads: "An introduction to multilevel modelling for intersectionality research: the MAIHDA Approach. 19th June 2025. Instructors: Prof George Leckie and Dr Andrew Bell. There are logos for Centre for multilevel modelling, NCRM, University of Sheffield, and UKRI

Come join George and I in Bristol, to learn about intersectional MAIHDA! bristol.ac.uk/cmm/software... @ncrm.ac.uk

04.03.2025 14:50 β€” πŸ‘ 3    πŸ” 3    πŸ’¬ 0    πŸ“Œ 0
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It’s my first project too! In fact, it’s also my first in epidemiology since I come from philosophy. :) I find stratified graphs based on social categories (like HernΓ‘ndez-Yumar, 2018) really interesting.

22.11.2024 13:09 β€” πŸ‘ 3    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0

A little story about this article & how teachers make a difference:

In 2013, I was a student in a social epidemiology class taught by the esteemed David Williams. He observed, with some frustration while we looked at a series of graphs, that we often lump people into the β€œHispanic” category β€” 1/

14.02.2025 01:03 β€” πŸ‘ 6    πŸ” 2    πŸ’¬ 1    πŸ“Œ 0
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NCRM resource | Multilevel models to study intersectionality by Andrew Bell and George Leckie Multilevel models allow researchers to analyse data that has a clustered structure such as pupils nested within schools, or individuals within neighbourhoods. Recently, a version of multilevel models

George Leckie and I have created a new short MAIHDA tutorial, with videos and practical exercises:

www.ncrm.ac.uk/resources/on...

It's based on our tutorial paper in SSM Pop Health, but shorter and more interactive.

Hope it's helpful! @ncrm.ac.uk

30.01.2025 12:33 β€” πŸ‘ 6    πŸ” 4    πŸ’¬ 0    πŸ“Œ 0
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A tutorial for conducting intersectional multilevel analysis of individual heterogeneity and discriminatory accuracy (MAIHDA) Intersectional multilevel analysis of individual heterogeneity and discriminatory accuracy (I-MAIHDA) is an innovative approach for investigating ineq…

Starting out using #intersectional MAIHDA analyses, so need to dig into this great tutorial paper by @clarerevans.bsky.social , Leckie, Subramanian, @andrewjdbell.bsky.social Juan Merlo πŸ‘

www.sciencedirect.com/science/arti...

03.12.2024 08:31 β€” πŸ‘ 22    πŸ” 7    πŸ’¬ 4    πŸ“Œ 2
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An analysis of intersectional disparities in alcohol consumption in the US Alcohol is one of the leading causes of preventable deaths in the United States (US). Prior research has demonstrated that alcohol consumption and rel…

New paper published in Social Science and Medicine 'An analysis of intersectional disparities in alcohol consumption in the US'. Led by @sophiebright.bsky.social, this study identifies several understudied groups who may have higher alcohol consumption than traditional methods would suggest.

19.11.2024 11:23 β€” πŸ‘ 5    πŸ” 8    πŸ’¬ 0    πŸ“Œ 0
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Psychological researchers are interested in how things change over time and routinely make claims about, for example, age effects (e.g., personality changes with age) or cohort effects (e.g., differences in intelligence between cohorts). The age-period-cohort identification problem means that these claims are not possible based on the data alone: Any possible temporal pattern can be explained by an infinite number of combinations of age, period, and cohort effects. This concern holds regardless of the study designβ€”it also applies to longitudinal designs covering multiple cohortsβ€”and regardless of the number of observations availableβ€”it also applies if we observe the whole population. Researchers rely on statistical models that impose assumptions to pick one specific combination of effects. But these assumptions are often opaque and researchers may be unaware of them, resulting in a lack of scrutiny. Here,...

Abstract Psychological researchers are interested in how things change over time and routinely make claims about, for example, age effects (e.g., personality changes with age) or cohort effects (e.g., differences in intelligence between cohorts). The age-period-cohort identification problem means that these claims are not possible based on the data alone: Any possible temporal pattern can be explained by an infinite number of combinations of age, period, and cohort effects. This concern holds regardless of the study designβ€”it also applies to longitudinal designs covering multiple cohortsβ€”and regardless of the number of observations availableβ€”it also applies if we observe the whole population. Researchers rely on statistical models that impose assumptions to pick one specific combination of effects. But these assumptions are often opaque and researchers may be unaware of them, resulting in a lack of scrutiny. Here,...

New preprint! osf.io/preprints/ps...
The age-period-cohort problem is something that many researchers are vaguely aware of. There have been very cool advances in how to reason about it which don't seem to be well-known in psych. So, I've written a primer!

19.09.2024 08:52 β€” πŸ‘ 219    πŸ” 65    πŸ’¬ 7    πŸ“Œ 9
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Rereading @andrewjdbell.bsky.social's 2020 paper on APC analysis & this is such a great example of how plots imply certain interpretations of the data.

Same underlying data but depending on how you connect the lines, the implied age effect looks completely different.

24.06.2024 08:54 β€” πŸ‘ 14    πŸ” 8    πŸ’¬ 1    πŸ“Œ 0

@andrewjdbell is following 20 prominent accounts