What is the proper adjective for rates?
"..the learning rate is low/high.."
or
"..the learning rate is small/large.."
It seems that there are different opinions:
Numbers can be described using the metaphor of size (large vs small) or height (high vs low).
Answer to What's the difference between “large share” and “high share”?
“Large” and “small” are generally used to express variations or changes in size, dimensions, or mass. “High” and “low” are usually used to express levels or numerical values. “Large” and “small” are often mistakenly used where “high” and “low” would be better.
Springer.com: Large/small/high/low
Best Answer
The Oxford Collocations Dictionary suggests high/low for the 'speed/frequency' aspect of rate (the other aspect there is 'amount of money'). And also the adjectives are suggested: constant, expected, regular, steady, slow, fast, rapid, alarming, phenomenal, ever-increasing, rocketing, etc. In no aspect large or small are suggested (I guess those words are more typical for pure numbers of something).
An example of using high/low with learning rate.
https://towardsdatascience.com/understanding-learning-rates-and-how-it-improves-performance-in-deep-learning-d0d4059c1c10
A picture of a graph from that page with definitions of different learning rates (high/low/good):
https://cdn-images-1.medium.com/max/1600/0*uIa_Dz3czXO5iWyI.