Jan-Ole Koslik's Avatar

Jan-Ole Koslik

@olemole.bsky.social

PhD student πŸŽ“ in Statistics at Bielefeld University interested in doubly stochastic processes and their application to ecology πŸ¦…, sports 🏈, and finance πŸ“ˆ. Website: https://janoleko.github.io GitHub: https://github.com/janoleko

279 Followers  |  942 Following  |  13 Posts  |  Joined: 23.12.2024  |  1.7927

Latest posts by olemole.bsky.social on Bluesky

Fast Numerical Maximum Likelihood Estimation for Latent Markov Models A variety of latent Markov models, including hidden Markov models, hidden semi-Markov models, state-space models and continuous-time variants can be formulated and estimated within the same framework ...

The LaMa package provides a versatile framework for inference with latent Markov models, designed to make building such models fun and efficient.

Check out the vignettes and start building models! πŸ› οΈ
πŸ‘‰ janoleko.github.io/LaMa/

05.09.2025 12:10 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Our review paper on latent Markov models is now published in Statistical Modelling! πŸŽ‰ @rolandlangrock.bsky.social @SinaMews.

We discuss choosing the right time and space formulation and provide the R package πŸ“¦ LaMa for fast ⚑and flexible estimation.

πŸ“„ Paper: journals.sagepub.com/eprint/UETXX...

05.09.2025 12:06 β€” πŸ‘ 5    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
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Congrats @bluesky on 35m !

19.04.2025 03:01 β€” πŸ‘ 38934    πŸ” 3941    πŸ’¬ 495    πŸ“Œ 186
Fast Numerical Maximum Likelihood Estimation for Latent Markov Models A variety of latent Markov models, including hidden Markov models, hidden semi-Markov models, state-space models and continuous-time variants can be formulated and estimated within the same framework ...

All the relevant methodology is fully implemented πŸ› οΈ in my R package LaMa πŸ¦™:

janoleko.github.io/LaMa/

19.03.2025 16:35 β€” πŸ‘ 4    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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Hidden semi-Markov models with inhomogeneous state dwell-time distributions The well-established methodology for the estimation of hidden semi-Markov models (HSMMs) as hidden Markov models (HMMs) with extended state spaces is …

My paper is out! πŸŽ‰ I explore hidden semi-Markov models with covariate-dependent state dwell-time distributions β€” because sometimes Markov just isn’t enough.
Case study: Arctic muskox movement! πŸ¦¬πŸ“Š
πŸ”— www.sciencedirect.com/science/arti...

#stats #TimeSeries #HSMM #StatisticalEcology #rstats

19.03.2025 16:35 β€” πŸ‘ 9    πŸ” 3    πŸ’¬ 1    πŸ“Œ 0
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Rdatasets is a collection of 2300 free and documented datasets in CSV format. It's a great resource for teaching and exploration!

The new `get_dataset()` function from the {marginaleffects} πŸ“¦ allows you to search and load them directly in #Rstats.

vincentarelbundock.github.io/Rdatasets/ar...

14.02.2025 12:54 β€” πŸ‘ 101    πŸ” 28    πŸ’¬ 3    πŸ“Œ 0
Popular meme format, grandma labeled with "bluesky's public launch was one year ago today." Younger person helping her labeled with "sure grandma let's get you to bed."

Popular meme format, grandma labeled with "bluesky's public launch was one year ago today." Younger person helping her labeled with "sure grandma let's get you to bed."

happy first birthday to Bluesky, and what a year it's been!

with every day, the need for an open network that puts people first becomes increasingly clear. we're glad to be building this with you. after all, the heart of a social network is the people.

06.02.2025 17:49 β€” πŸ‘ 154626    πŸ” 13994    πŸ’¬ 3522    πŸ“Œ 1686
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The world is on πŸ”₯ -- and here's my first publication in an astronomy journal: iopscience.iop.org/article/10.3...

We combine Gaussian processes + hidden Markov models to efficiently detect stellar flares in one modelling step. πŸ§ͺ

31.01.2025 02:26 β€” πŸ‘ 39    πŸ” 9    πŸ’¬ 2    πŸ“Œ 1
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Could watch this animation all day 😍

Did you know that you can create GIFs with gganimate()? They can even be embedded in a latex PDF file and played via Adobe Acorbat Reader πŸ’₯

#ggplot #gganimate #datavisualisation #statisticalmodelling #finance #economics #quants

21.01.2025 13:56 β€” πŸ‘ 7    πŸ” 2    πŸ’¬ 1    πŸ“Œ 0
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I'm just saying this is syntatically correct #rstats code

16.01.2025 16:38 β€” πŸ‘ 119    πŸ” 21    πŸ’¬ 16    πŸ“Œ 10
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2024 @copernicusecmwf.bsky.social #climate data out today:

πŸ“ˆ 2024 - first year more than 1.5Β°C above pre-industrial; for ERA5 it was 1.6ΒΊC
🌑️ the past 10 years were the 10 warmest years on record
πŸ“ˆ 2024 was warmest year for all continental regions, except Antarctica and Australasia

🌍🌑️πŸ§ͺβš’οΈπŸŒŠ

10.01.2025 06:20 β€” πŸ‘ 156    πŸ” 107    πŸ’¬ 6    πŸ“Œ 6
On Theoretical Foundations of Diffusion Models
YouTube video by C3 Digital Transformation Institute On Theoretical Foundations of Diffusion Models

Quite a nice watch:
youtu.be/TE4R8bumI-Q?...

06.01.2025 21:01 β€” πŸ‘ 36    πŸ” 4    πŸ’¬ 0    πŸ“Œ 0
HMMotion: Using tracking data to predict coverage Explore and run machine learning code with Kaggle Notebooks | Using data from multiple data sources

Full kaggle notebook:

www.kaggle.com/code/rouvenm...

07.01.2025 14:10 β€” πŸ‘ 3    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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In this yearβ€˜s NFL Big Data Bowl 🏈 submission, @rmichels.bsky.social, Robert Bajons, and I employ hidden Markov models to uncover πŸ”Žguarding assignments and use this additional information to improve the prediction of defensive strategies. πŸ“Š
#bigdatabowl #rstats

07.01.2025 14:10 β€” πŸ‘ 8    πŸ” 1    πŸ’¬ 3    πŸ“Œ 0

Big Data Bowl submissions are due tomorrow

🚨🚨

The deadline is 11:59 PM UTC, which is 6:59 PM EST

🚨🚨

#BigDataBowl

06.01.2025 02:39 β€” πŸ‘ 8    πŸ” 2    πŸ’¬ 2    πŸ“Œ 0
Example

With a matrix

> x <- matrix(rnorm(20 * 500), nrow = 20, ncol = 500)
it is many times faster to calculate medians column by column using

> mu <- matrixStats::colMedians(x)
than using

> mu <- apply(x, MARGIN = 2, FUN = median)
Moreover, if performing calculations on a subset of rows and/or columns, using

> mu <- colMedians(x, rows = 33:158, cols = 1001:3000)
is much faster and more memory efficient than

> mu <- apply(x[33:158, 1001:3000], MARGIN = 2, FUN = median)

Example With a matrix > x <- matrix(rnorm(20 * 500), nrow = 20, ncol = 500) it is many times faster to calculate medians column by column using > mu <- matrixStats::colMedians(x) than using > mu <- apply(x, MARGIN = 2, FUN = median) Moreover, if performing calculations on a subset of rows and/or columns, using > mu <- colMedians(x, rows = 33:158, cols = 1001:3000) is much faster and more memory efficient than > mu <- apply(x[33:158, 1001:3000], MARGIN = 2, FUN = median)

The {matrixStats} #RStats πŸ“¦ β€œprovides highly optimized functions for computing common summaries over rows and columns of matrices, e.g. rowQuantiles(). There are also functions that operate on vectors.”
By @henrikbengtsson.bsky.social
github.com/HenrikBengts...

03.01.2025 12:43 β€” πŸ‘ 19    πŸ” 5    πŸ’¬ 0    πŸ“Œ 0

I crunch a lot of numbers to ultimately tell people β€žyeah this thing may or may not happen idkβ€œ.

30.12.2024 22:25 β€” πŸ‘ 4    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

πŸ₯²πŸ₯²πŸ₯²

30.12.2024 19:37 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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2024 In Review - Bluesky It’s been a big year for Bluesky! Let's take a look back at everything that’s happened in the past year.

What a year! Bluesky opened its doors just last February. Since then, we opened federation, launched video, rolled out trending topics, and a whole lot more.

Happy New Year, and here’s to a great year ahead! πŸŽ‰

30.12.2024 19:08 β€” πŸ‘ 51597    πŸ” 5537    πŸ’¬ 1688    πŸ“Œ 369

Oh yeah, hurts every time πŸ˜‚

30.12.2024 16:41 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
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Every time it’s called a classifier, somewhere, a statistician dies. πŸ˜΅β€πŸ’«
#stats #ML

30.12.2024 14:10 β€” πŸ‘ 15    πŸ” 1    πŸ’¬ 5    πŸ“Œ 0
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Linear Model and Extensions I developed the lecture notes based on my ``Linear Model'' course at the University of California Berkeley over the past seven years. This book provides an intermediate-level introduction to the linea...

Ooooooo

arxiv.org/abs/2401.00649

28.12.2024 14:37 β€” πŸ‘ 32    πŸ” 5    πŸ’¬ 1    πŸ“Œ 0
Post image 29.12.2024 02:40 β€” πŸ‘ 63    πŸ” 7    πŸ’¬ 2    πŸ“Œ 2
Boromir from Lord of the Rings saying "ONE DOES NOT SIMPLY INSTALL PYTHON"

Boromir from Lord of the Rings saying "ONE DOES NOT SIMPLY INSTALL PYTHON"

14.11.2024 14:21 β€” πŸ‘ 34    πŸ” 5    πŸ’¬ 0    πŸ“Œ 1
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Does probability exist? Probably not β€” but it is useful to act as if it does.

www.nature.com/articles/d41...

16.12.2024 12:27 β€” πŸ‘ 20    πŸ” 7    πŸ’¬ 1    πŸ“Œ 1

May I be added? Working a lot on hidden Markov models for movement ecology. πŸ˜„

27.12.2024 19:32 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0
Fast Numerical Maximum Likelihood Estimation for Latent Markov Models A variety of latent Markov models, including hidden Markov models, hidden semi-Markov models, state-space models and continuous-time variants can be formulated and estimated within the same framework ...

πŸ› οΈ The paper is complemented by the R package LaMa, a fast ⚑ and flexible framework for estimating latent Markov models, designed to make building such models much easier for everyone!

πŸ‘‰ janoleko.github.io/LaMa/

Check out the vignettes and start building models! πŸ—οΈ

25.12.2024 16:30 β€” πŸ‘ 4    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0
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How to build your latent Markov model -- the role of time and space Statistical models that involve latent Markovian state processes have become immensely popular tools for analysing time series and other sequential data. However, the plethora of model formulations, t...

Sina Mews, Roland Langrock, and I have updated πŸ†• our review paper!
It offers a comprehensive overview on choosing the right time ⏰ and space πŸ“ formulation for latent Markov models, providing a unifying perspective on discrete- and continuous-time HMMs, SSMs and MMPPs.

πŸ‘‰ arxiv.org/abs/2406.19157

25.12.2024 16:30 β€” πŸ‘ 16    πŸ” 6    πŸ’¬ 1    πŸ“Œ 1
A log likelihood is shown. The quantities for the score, wald, and likelihood tests are illustrated with respect to the log likelihood.

A log likelihood is shown. The quantities for the score, wald, and likelihood tests are illustrated with respect to the log likelihood.

You will be visited by three ghosts

25.12.2024 15:00 β€” πŸ‘ 258    πŸ” 31    πŸ’¬ 6    πŸ“Œ 3
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Quarto An open source technical publishing system for creating beautiful articles, websites, blogs, books, slides, and more. Supports Python, R, Julia, and JavaScript.

I feel like not enough people know about Quarto for creating documents.

How it works: Write in markdown and use Quarto to convert it to html, pdf, epub, ...

I produce my books with Quarto (web + ebook + print version). But you can also use it for websites, reports, dashboards, ...

quarto.org

24.11.2024 10:24 β€” πŸ‘ 181    πŸ” 26    πŸ’¬ 16    πŸ“Œ 5

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