Category: Machine learning

Delay Embedding: Learning hidden coordinates in cell biology

Trajectories are golden information in the study of dynamical systems like cells.  If we can follow individual cells in time, then we can learn what events precede others and in principle infer all kinds of wonderful mechanistic information.

The problem is that measurements that reveal high-dimensional omics information for single cells require killing the cells, whereas observing cells in real time via video microscopy doesn’t reveal too much molecular information.  Although modern live-cell microscopy techniques enable labeling specific cellular proteins to reveal their spatial and temporal intra-cellular behavior, this is limited to a literal handful of proteins (at once).  And there’s always the worry that the labels may alter the behavior of cells.

So the question is, How can we learn detailed information for single cells as they change and move in time?  In other words, can we learn about (apparently) hidden information?

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Machine Learning for Outsiders 2 – Cross validation and learning curves

Having covered the very basics of machine learning (ML) in a previous post, I want to introduce you to an essential conceptual framework embodied in a simple graph called the “learning curve” or “training curve.” This graph can be made to aid evaluation of any ML project, and is invaluable for non-expert evaluation of a project. The learning curve is closely related to cross-validation, which we will also discuss.
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Machine Learning for Outsiders 1 – Very basics

I want to introduce machine learning (ML) to people outside the field, both non-mathematical scientists totally new to machine learning and quantitative folks who are novices. My qualifications for this are that I’m an outsider to ML myself, maybe an “advanced beginner” – with several years of experience. As I have learned ML, I try to keep an eye out for what’s important and what isn’t.
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