alt Hacker NewsWhy are we reinventing wheels and giving them bad names
This is an exponential moving average aka first order average and has been used for decades. It's introductory material in any DSP class.
There are multiple varying derivations of the coefficients that have different meanings, the best one for this example would be as an approximation of an N-point moving average (derivation of that is an exercise to the reader, but it's like five minutes of whiteboarding)
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This is a nonlinear filter because of the way alpha is determined. Since this is in SIGCHI, I assume the actual novelty here is "this filter has behavior that feels right to interactive users, (and is also computationally cheap)".
Your criticism is the reason for the name though
Yeah, what the hell? This is the most basic IIR filter in existence.
But an N-point moving average isn't adaptive, no? It has lag, this filter can adjust the smoothing effect to reduce lag. The exponential moving average is just one part of the presented filter, that's not the innovation here.