Rounding-step experiment

SupportPointSplitter optimizes continuous support points and then maps each one to its nearest unclaimed data row (select_nearest, sequential nearest-neighbor, Joseph & Vakayil 2022). Points are initialized at a random sample of data rows, jittered by 0.1% of the per-dimension range (_initial_points). This experiment measures, per (dataset, N), how far the optimizer moves the points relative to the spacing between data rows, whether that leaves the rounded selection identical to the initial sample, and whether starting away from data rows (uniform in the bounding box, or heavy jitter around the initial sample) changes the outcome. It also reproduces run.jl's own datasplit path for support points · gaussian (rows marked "(datasplit path)"): datasplit resolves the :median bandwidth from the splitter's rng before _initial_points draws from it, so its initial sample is a different draw from the fresh-rng "initial sample" row above it. * marks iteration counts that hit max_iterations without converging. rows kept counts selected rows shared with the relevant initial sample (the fresh-rng one, or init_ds for the "(datasplit path)" row) out of the method's own subset size.

datasetNmethoditerationsmedian movecontinuous MMDrows kepttest-vs-train MMDtest-vs-train energy distance
mixture-2d1000random (5 seeds)––––0.002580.012
mixture-2d1000initial sample––––0.00120.00642
mixture-2d1000initial sample (datasplit path)––––0.00120.00642
mixture-2d1000support points · gaussian (datasplit path)25––68/2003.21e-50.00264
mixture-2d1000support points · gaussian250.09135.71e-768/2003.21e-50.00264
mixture-2d1000support points · energy500*0.1091.81e-737/2001.57e-60.000323
mixture-2d1000gaussian, uniform-box init950.2264.17e-644/2002.14e-50.00837
mixture-2d1000gaussian, heavy-jitter init1170.4122.26e-643/2002.4e-50.00843
normal-10d1000random (5 seeds)––––0.002270.0255
normal-10d1000initial sample––––0.002240.0247
normal-10d1000initial sample (datasplit path)––––0.002240.0247
normal-10d1000support points · gaussian (datasplit path)138––200/2000.002240.0247
normal-10d1000support points · gaussian1380.5751.19e-5200/2000.002240.0247
normal-10d1000support points · energy500*0.6822.28e-5185/2000.001870.0215
normal-10d1000gaussian, uniform-box init962.992.4e-539/2000.003330.0325
normal-10d1000gaussian, heavy-jitter init1393.251.84e-546/2000.003810.0372
uniform-5d1000random (5 seeds)––––0.002170.0173
uniform-5d1000initial sample––––0.001940.0161
uniform-5d1000initial sample (datasplit path)––––0.001940.0161
uniform-5d1000support points · gaussian (datasplit path)38––199/2000.001890.0158
uniform-5d1000support points · gaussian380.2486.08e-6199/2000.001890.0158
uniform-5d1000support points · energy500*0.4911.89e-696/2000.0002550.0047
uniform-5d1000gaussian, uniform-box init640.3544.82e-637/2000.0003160.00685
uniform-5d1000gaussian, heavy-jitter init710.5873.9e-636/2000.0002430.0067
t3-3d1000random (5 seeds)––––0.003750.0161
t3-3d1000initial sample––––0.003970.0149
t3-3d1000initial sample (datasplit path)––––0.003970.0149
t3-3d1000support points · gaussian (datasplit path)104––114/2000.0008410.00586
t3-3d1000support points · gaussian1040.1546.7e-5114/2000.0008410.00586
t3-3d1000support points · energy500*0.2444.4e-542/2000.0001160.00163
t3-3d1000gaussian, uniform-box init200*2.750.10540/2000.05780.234
t3-3d1000gaussian, heavy-jitter init200*3.180.097843/2000.04490.151
mixture-2d10000random (5 seeds)––––0.0001660.000885
mixture-2d10000initial sample––––0.0002670.00125
mixture-2d10000initial sample (datasplit path)––––0.0001680.000813
mixture-2d10000support points · gaussian (datasplit path)14––675/20001.74e-60.0003
mixture-2d10000support points · gaussian380.04051.38e-7504/20006.36e-70.000493
mixture-2d10000support points · energy500*0.04212.25e-5411/20003.2e-50.000173
mixture-2d10000support points · energy, full data100*0.03624.79e-8437/20001.88e-71.98e-5
mixture-2d10000gaussian, uniform-box init780.2235.01e-6385/20007.85e-60.00735
mixture-2d10000gaussian, heavy-jitter init100*0.5224.42e-6403/20009.18e-60.0084
normal-10d10000random (5 seeds)––––0.0001640.00208
normal-10d10000initial sample––––0.0002150.0025
normal-10d10000initial sample (datasplit path)––––0.0002890.00299
normal-10d10000support points · gaussian (datasplit path)35––2000/20000.0002890.00299
normal-10d10000support points · gaussian520.1442.29e-62000/20000.0002150.0025
normal-10d10000support points · energy500*0.297.72e-52000/20000.0002150.0025
normal-10d10000support points · energy, full data100*0.1991.88e-62000/20000.0002150.0025
normal-10d10000gaussian, uniform-box init100*4.061.84e-5395/20000.0030.0258
normal-10d10000gaussian, heavy-jitter init100*4.252.33e-5409/20000.002680.0243
uniform-5d10000random (5 seeds)––––0.000160.00146
uniform-5d10000initial sample––––0.0001510.00147
uniform-5d10000initial sample (datasplit path)––––0.0002440.00187
uniform-5d10000support points · gaussian (datasplit path)40––1998/20000.0002430.00187
uniform-5d10000support points · gaussian400.08455.1e-71998/20000.0001510.00146
uniform-5d10000support points · energy500*0.1954.41e-51731/20007.24e-50.000844
uniform-5d10000support points · energy, full data100*0.1429.03e-81929/20000.0001310.0013
uniform-5d10000gaussian, uniform-box init440.1066.08e-7378/20003.37e-50.000723
uniform-5d10000gaussian, heavy-jitter init390.4061.06e-6404/20001.48e-50.000695
t3-3d10000random (5 seeds)––––0.0003050.00151
t3-3d10000initial sample––––0.0001610.000919
t3-3d10000initial sample (datasplit path)––––0.0002190.00114
t3-3d10000support points · gaussian (datasplit path)55––1521/20008.06e-50.000583
t3-3d10000support points · gaussian430.04485.06e-61605/20007.1e-50.000575
t3-3d10000support points · energy500*0.08956.52e-5789/20004.82e-50.000262
t3-3d10000support points · energy, full data100*0.07013.4e-61105/20002.87e-50.00023
t3-3d10000gaussian, uniform-box init100*0.4730.477383/20000.2270.517
t3-3d10000gaussian, heavy-jitter init100*0.4650.484382/20000.230.514
datasetNmedian nearest-neighbor spacing
mixture-2d10000.036
normal-10d10001.8
uniform-5d10000.621
t3-3d10000.161
mixture-2d100000.0112
normal-10d100001.37
uniform-5d100000.376
t3-3d100000.0772