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High dimensional geometry is transforming the MRI industry (2017) [pdf]

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Re: High dimensional geometry is transforming the MRI industry (2017) [pdf]

#31

Post by lostlogin »

Vexs wrote: post #14

It's worth reading this one to the end- the point of this paper isn't about the math involved, it's that this math was the result of the federal funding of maths research. > The cost-benefit ratio of Mathematical research has been off-scale. The Federal government spends about $250 Million/year on mathematics research. Yet in the US there are 40 Million MRI scans per year, incurring tens of billions in Medicaid, Medi…

But have the scans got cheaper? It’s possibly that acceleration techniques have prevented the cost being greater, but key parts of the cost are not getting cheaper. Staffing costs are just so high.

Pricing a scan based on scanner time doesn’t really work.

Re: High dimensional geometry is transforming the MRI industry (2017) [pdf]

#32

Post by lostlogin »

CGMthrowaway wrote: post #20
Lerc wrote: post #15

Earlier quoted context omitted.

It sounds like it's a claim along the lines that you can't tell "I love Lucy" is on because you are listening to the audio and not looking at the screen.

fMRI is a step above dowsing rods. It's plugging a multimeter into an outlet and guessing what type and brand of appliances you are running in your house.

Try it with a crude task - eg finger tapping. It’s pretty convincing.

Re: High dimensional geometry is transforming the MRI industry (2017) [pdf]

#33

Post by srean »

throwaway34018 wrote: post #13

Having worked through Geometric Tomography by Gardner, one of the big names in the field, I am pretty confident in asserting that the folks in the field have little to no interest in tomography or other applications. It's merely a grant winning ruse. The same field rebrands as "high dimensional probability/stats" by casting the uniform measure on convex bodies in the language of log-concave densities, but you talk to…

> by casting the uniform measure on convex bodies in the language of log-concave densities

Can you tell more ? I find the idea very intriguing. I don't know of the connection between the two.

Re: High dimensional geometry is transforming the MRI industry (2017) [pdf]

#35

Post by mmooss »

davidkipstar wrote: post #6

It's a nice review but the end reads like a funding pitch. The most important Mathematicians like donoho and Tao in the US seem to currently experience budget cuts and start to address the public.

It may be a funding pitch, explicitly. It's not a paper - it has no abstract, no citations, works cited, etc.

Re: High dimensional geometry is transforming the MRI industry (2017) [pdf]

#37

Post by aaron695 »

Vexs wrote: post #14

It's worth reading this one to the end- the point of this paper isn't about the math involved, it's that this math was the result of the federal funding of maths research. > The cost-benefit ratio of Mathematical research has been off-scale. The Federal government spends about $250 Million/year on mathematics research. Yet in the US there are 40 Million MRI scans per year, incurring tens of billions in Medicaid, Medi…

[dead]

Re: High dimensional geometry is transforming the MRI industry (2017) [pdf]

#38

Post by skew-aberration »

FL33TW00D wrote: post #8
yummybrainz wrote: post #7

If folks are interested, I recently published a paper [1] demonstrating that fMRI activity in the visual cortex is remarkably high-dimensional! Specifically, using a linear approach (like PCA, but slightly fancier), we find that stimulus-related information is present along many, many dimensions of the neural response---much more than previously expected/reported. [1] https://journals.plos.org/ploscompbiol/article?id…

Hasn't fMRI as a whole been called into question? https://www.nature.com/articles/s41593-025-02132-9

I was expecting a link to this paper https://www.sciencedirect.com/science/article/abs/pii/S10538...

Re: High dimensional geometry is transforming the MRI industry (2017) [pdf]

#39

Post by aix1 »

zdragnar wrote: post #29
BigTTYGothGF wrote: post #25

Earlier quoted context omitted.

I was at a talk maybe 15 years ago in which the speaker gave pretty convincing evidence that given a time series of voltages you could learn a lot of things about what kind of appliances you've got running.

There are a lot of devices that have reasonably distinct patterns to their power consumption. Motors- especially well pumps, but also large central air fans and some others- are going to look very different from a microwave or vacuum cleaner or refrigerator, especially if you have time of day on your readings. Constant lower draw devices- chargers, lights, speakers and such- are going to be harder to distinguish, tho…

Turns out it's a (somewhat) active area of research.

https://ubicomplab.cs.washington.edu/pdfs/electrisense.pdf

https://www.researchgate.net/publication/266461208_Multimedi...

https://www.mdpi.com/1996-1073/14/9/2485

Re: High dimensional geometry is transforming the MRI industry (2017) [pdf]

#40

Post by dooglius »

rtkwe wrote: post #17
Vexs wrote: post #14

It's worth reading this one to the end- the point of this paper isn't about the math involved, it's that this math was the result of the federal funding of maths research. > The cost-benefit ratio of Mathematical research has been off-scale. The Federal government spends about $250 Million/year on mathematics research. Yet in the US there are 40 Million MRI scans per year, incurring tens of billions in Medicaid, Medi…

It's the thing people don't get when they see odd studies being funded and try to judge if they're worthy of being funded. Either it's just they don't understand where the study fits into a larger problem or simply that esoteric studies sometimes leads to surprising findings that are far more useful than anyone could reasonable predict.

It would be instructive to actually look at the studies in question and whether or not they were odd or esoteric.
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