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Daniel Roelfs

@danielroelfs.com.bsky.social

Data Scientist - PhD in computational neuroscience - he/him - #rstats / #python danielroelfs.com

318 Followers  |  103 Following  |  19 Posts  |  Joined: 04.12.2023  |  2.0238

Latest posts by danielroelfs.com on Bluesky

Plot showing a time series for 3 datapoints, two cases (where vineyard replanting happened at different timepoints in 2018 and 2021) and a control plot

Plot showing a time series for 3 datapoints, two cases (where vineyard replanting happened at different timepoints in 2018 and 2021) and a control plot

Using publicly accessible data from the EU's Copernicus satellite project I did some (very) simple analysis on vineyard health over the course of a few years and showed how one might use it to measure recovery after a plot is razed due to illness or other planned or unplanned damage to the plants 🌱

13.05.2025 17:22 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
Daniel Roelfs Remote sensing of vineyard health

✨New blog post✨

Remote sensing of vineyard health πŸ‡

I felt inspired by a data visualization exhibition I visited a while ago and decided to try my hand at remote sensing and analyzed some satellite images in Python.

danielroelfs.com/posts/remote...

13.05.2025 17:22 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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What’s New in R: April 28, 2025 Explore the latest in R, including a new package for U.S. elevation data, updates in R 4.5.0 like the use() function, and a guide to creating FT data viz.

This week on What's New in R:

βœ… A new R package by Joey Marshall for accessing elevation data
βœ… Overview of what’s new in R 4.5, compiled by Russ Hyde of Jumping Rivers
βœ… A guide to replicating Financial Times-style data visualizations, by Daniel Roelfs

Read the issue: buff.ly/Y4HwU4g

#rstats

28.04.2025 15:02 β€” πŸ‘ 4    πŸ” 2    πŸ’¬ 0    πŸ“Œ 0
Daniel Roelfs Learning data viz from the best: the Financial Times

I admire John Burn-Murdoch's ability to create really effective data visualizations. So much that I took the liberty of breaking down one of his recent figures that made the rounds and see if I could recreate it in R using only ggplot. Here's the breakdown:

danielroelfs.com/blog/financi...

16.04.2025 19:57 β€” πŸ‘ 9    πŸ” 2    πŸ’¬ 0    πŸ“Œ 1
Type of GitHub tile plot using Strava running data where each tile represents the kilometers run during the day. Sparse data with some data visualisation issues around the beginning and end of the year due to overlapping week numbers and because not all years start on Monday

Type of GitHub tile plot using Strava running data where each tile represents the kilometers run during the day. Sparse data with some data visualisation issues around the beginning and end of the year due to overlapping week numbers and because not all years start on Monday

It also let's us create some new nerdy plots like a GitHub tile plot, but for runs across the year:

30.12.2024 21:40 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
Cumulative plot showing the cumulative kilometers ran during the 2022 (in yellow), 2023 (in pink), and 2024 (in 2024)

Cumulative plot showing the cumulative kilometers ran during the 2022 (in yellow), 2023 (in pink), and 2024 (in 2024)

This let's you (re)create some analysis that is only available for subscription users and create plots that aren't available in Strava at all

30.12.2024 21:40 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
Daniel Roelfs Strava Data Analysis using Python and R

Anyone that uses Strava has access to a large, self-generated (!), dataset 🧑. And at the end of the year it's quite fun to try to parse something interesting and relevant from that dataset: danielroelfs.com/blog/strava-...

30.12.2024 21:40 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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Don’t believe the hype: AGI is far from inevitable | Radboud University Will AI soon surpass the human brain? If you ask employees at OpenAI, Google DeepMind and other large tech companies, it is inevitable. However, researchers at Radboud University and other institutes ...

See also www.ru.nl/en/research/...

01.12.2024 16:21 β€” πŸ‘ 64    πŸ” 16    πŸ’¬ 3    πŸ“Œ 0
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GitHub - MichelNivard/awesome-complex-trait-genetics: A list of awesome tools for complex trait genetics. A list of awesome tools for complex trait genetics. - MichelNivard/awesome-complex-trait-genetics

🚨 This will become a curated list of awesome tools for complex trait genetics, **add yours**! it may become a review in which case those who contribute are invited as co-authors.

28.11.2024 09:21 β€” πŸ‘ 73    πŸ” 40    πŸ’¬ 7    πŸ“Œ 4

The slide decks were optimised for the screen in the auditorium (which was 1920x1200) so the slides are best viewed on a screen of that size, or perhaps on another 16x10 screen.

24.11.2024 14:02 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
PhD Defense

Slides for the trial lecture and disputation are available here: slides.danielroelfs.app/2024-11-19-p... Perhaps some of my illustrations in either slide deck are useful for others in the imaging-genetics or psychiatric genetics field! 😊

24.11.2024 13:42 β€” πŸ‘ 1    πŸ” 1    πŸ’¬ 1    πŸ“Œ 0
Photo of myself presenting at the trial lecture with a slide on twin-based studies in the background

Photo of myself presenting at the trial lecture with a slide on twin-based studies in the background

Photo of myself during the disputation with a "thank you" slide in the background

Photo of myself during the disputation with a "thank you" slide in the background

Last Tuesday I defended my PhD in computational neuroscience and psychiatric genetics πŸ₯³

PhD theses are rarely read outside of the supervisors and committee, so I tried to write it in an accessible way and published a digital version here: thesis.danielroelfs.app

- Daniel Roelfs, PhD

24.11.2024 13:42 β€” πŸ‘ 9    πŸ” 2    πŸ’¬ 1    πŸ“Œ 0

Mendelian randomization users, what should I call a polygenic score created for and used with MR?
I find PGS/PGI confusing to newcomers as not all ways of creating a PGS will do.
Would it be clearer to call this score an allelic score instead? Or something else?

22.07.2024 14:19 β€” πŸ‘ 0    πŸ” 2    πŸ’¬ 1    πŸ“Œ 0
RELX Group Lobbying Profile RELX Group spent $3,180,000 lobbying in 2023. See the details.

Elsevier's parent company RELX has spent about as much money lobbying US politicians in 2023 as large financial companies like JPMorgan Chase and massive car companies like Ford www.opensecrets.org/federal-lobb...

09.05.2024 10:54 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
Barplot showing the profit margins for a number of scientific publishers and other companies for comparison

Barplot showing the profit margins for a number of scientific publishers and other companies for comparison

Scientific publishing (Elsevier and Springer-Nature specifically) has higher profit margins than some of the biggest tech companies such as Apple and Google (up to 38% 🀯) . These margins have been stable for years

09.05.2024 10:50 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
Post image

Open access fees for some of the biggest journals have exceeded $11.000 (120.000 NOK) PER ARTICLE.

09.05.2024 10:47 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
Daniel Roelfs Daniel Roelfs' personal website

It's hard to explain why scientific publishers like Elsevier and Springer-Nature make the kind of money they do.

So hard that I did the data analysis and wrote it down so I could easily share it and perhaps help others understand how broken the system is:

danielroelfs.com/blog/the-mon...

09.05.2024 10:46 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Preprint available here: www.medrxiv.org/content/10.1...
Data and code available here: github.com/norment/open...

08.01.2024 19:21 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

The findings in this paper provide some additional genetic support for the dysconnectivity hypothesis in a number of psychiatric disorders as well as identifying potential targets for future etiological studies

08.01.2024 19:06 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

This allowed us to find biologically relevant loci (involved in synaptic development and functioning) and discover shared genetic architecture with a number of psychiatric disorders. These overlapping loci are in turn also associated with a number of biologically relevant biological processes

08.01.2024 19:04 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

fMRI has quite a lot of noise to say it kindly, so deploying a multivariate approach to look at global resting state functioning instead of individual networks really helped to capture relevant genetic variance.

08.01.2024 19:00 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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Genetic overlap between multivariate measures of human functional brain connectivity and psychiatric... Using a multivariate approach in a sample from the UK Biobank, the authors examine the genetic relationships between measures of functional connectivity and psychiatric disorders.

Our latest paper is now published in Nature Mental Health ✨

We applied a multivariate GWAS implemented through the Bayesian framework in MOSTest on UK Biobank fMRI data and found widespread overlap with psychiatric disorders

www.nature.com/articles/s44...

08.01.2024 18:59 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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Society For Neuroscience - Nonprofit Explorer - ProPublica Since 2013, the IRS has released data culled from over 1.8 million nonprofit tax filings. Use this database to find organizations and see details like their executive compensation, revenue and expense...

Are people (and neuroscientists in particular) aware that that the SfN chair has a total compensation of about $960.000? That's about 4% of total revenue. I've left academia a while ago and Twitter is terrible since the takeover so maybe I missed some discourse, but it feels that's a lot? Source:

14.12.2023 19:01 β€” πŸ‘ 4    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

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