|
| 1 | +{ |
| 2 | + "cells": [ |
| 3 | + { |
| 4 | + "cell_type": "code", |
| 5 | + "execution_count": 3, |
| 6 | + "id": "8266c456-f304-442e-97f6-a41659b3eef7", |
| 7 | + "metadata": {}, |
| 8 | + "outputs": [ |
| 9 | + { |
| 10 | + "data": { |
| 11 | + "text/plain": [ |
| 12 | + "'\\nvariance\\nmethods for calculating variance, including some of the latest techniques from research and scholarly articles.\\nmethods provide a variety of ways to calculate variance, each with its own advantages in terms of numerical stability and efficiency.\\n'" |
| 13 | + ] |
| 14 | + }, |
| 15 | + "execution_count": 3, |
| 16 | + "metadata": {}, |
| 17 | + "output_type": "execute_result" |
| 18 | + } |
| 19 | + ], |
| 20 | + "source": [ |
| 21 | + "'''\n", |
| 22 | + "variance\n", |
| 23 | + "methods for calculating variance, including some of the latest techniques from research and scholarly articles.\n", |
| 24 | + "methods provide a variety of ways to calculate variance, each with its own advantages in terms of numerical stability and efficiency.\n", |
| 25 | + "'''" |
| 26 | + ] |
| 27 | + }, |
| 28 | + { |
| 29 | + "cell_type": "code", |
| 30 | + "execution_count": 5, |
| 31 | + "id": "41fa44c8-e4f9-468b-9df9-431aa9fb4568", |
| 32 | + "metadata": {}, |
| 33 | + "outputs": [], |
| 34 | + "source": [ |
| 35 | + "def naive_variance(data):\n", |
| 36 | + " n = len(data)\n", |
| 37 | + " if n < 2:\n", |
| 38 | + " return float('nan')\n", |
| 39 | + " mean = sum(data) / n\n", |
| 40 | + " variance = sum((x - mean) ** 2 for x in data) / (n - 1)\n", |
| 41 | + " return variance" |
| 42 | + ] |
| 43 | + }, |
| 44 | + { |
| 45 | + "cell_type": "code", |
| 46 | + "execution_count": 7, |
| 47 | + "id": "b466bebd-ec93-43d1-8650-6953266c3b3c", |
| 48 | + "metadata": {}, |
| 49 | + "outputs": [], |
| 50 | + "source": [ |
| 51 | + "def two_pass_variance(data):\n", |
| 52 | + " n = len(data)\n", |
| 53 | + " if n < 2:\n", |
| 54 | + " return float('nan')\n", |
| 55 | + " mean = sum(data) / n\n", |
| 56 | + " variance = sum((x - mean) ** 2 for x in data) / n\n", |
| 57 | + " return variance\n" |
| 58 | + ] |
| 59 | + }, |
| 60 | + { |
| 61 | + "cell_type": "code", |
| 62 | + "execution_count": 9, |
| 63 | + "id": "abbd8ba7-1b7f-4975-b321-5ae332ea02c5", |
| 64 | + "metadata": {}, |
| 65 | + "outputs": [], |
| 66 | + "source": [ |
| 67 | + "def welford_online(data):\n", |
| 68 | + " n = 0\n", |
| 69 | + " mean = 0\n", |
| 70 | + " M2 = 0\n", |
| 71 | + " for x in data:\n", |
| 72 | + " n += 1\n", |
| 73 | + " delta = x - mean\n", |
| 74 | + " mean += delta / n\n", |
| 75 | + " delta2 = x - mean\n", |
| 76 | + " M2 += delta * delta2\n", |
| 77 | + " if n < 2:\n", |
| 78 | + " return float('nan')\n", |
| 79 | + " variance = M2 / (n - 1)\n", |
| 80 | + " return variance" |
| 81 | + ] |
| 82 | + }, |
| 83 | + { |
| 84 | + "cell_type": "code", |
| 85 | + "execution_count": 11, |
| 86 | + "id": "4c140d97-0ed0-404a-bc3c-354216fd5ab8", |
| 87 | + "metadata": {}, |
| 88 | + "outputs": [], |
| 89 | + "source": [ |
| 90 | + "def online_compensated(data):\n", |
| 91 | + " n = 0\n", |
| 92 | + " mean = 0\n", |
| 93 | + " M2 = 0\n", |
| 94 | + " for x in data:\n", |
| 95 | + " n += 1\n", |
| 96 | + " delta = x - mean\n", |
| 97 | + " mean += delta / n\n", |
| 98 | + " delta2 = x - mean\n", |
| 99 | + " M2 += delta * delta2\n", |
| 100 | + " if n < 2:\n", |
| 101 | + " return float('nan')\n", |
| 102 | + " variance = M2 / (n - 1)\n", |
| 103 | + " return variance" |
| 104 | + ] |
| 105 | + }, |
| 106 | + { |
| 107 | + "cell_type": "code", |
| 108 | + "execution_count": 13, |
| 109 | + "id": "ece7b688-850c-4190-9b8a-ab70f4efde9f", |
| 110 | + "metadata": {}, |
| 111 | + "outputs": [], |
| 112 | + "source": [ |
| 113 | + "def incremental_variance(data):\n", |
| 114 | + " n = 0\n", |
| 115 | + " mean = 0\n", |
| 116 | + " M2 = 0\n", |
| 117 | + " for x in data:\n", |
| 118 | + " n += 1\n", |
| 119 | + " delta = x - mean\n", |
| 120 | + " mean += delta / n\n", |
| 121 | + " delta2 = x - mean\n", |
| 122 | + " M2 += delta * delta2\n", |
| 123 | + " if n < 2:\n", |
| 124 | + " return float('nan')\n", |
| 125 | + " variance = M2 / (n - 1)\n", |
| 126 | + " return variance" |
| 127 | + ] |
| 128 | + }, |
| 129 | + { |
| 130 | + "cell_type": "code", |
| 131 | + "execution_count": 15, |
| 132 | + "id": "51664d40-4d2b-4936-a0eb-d25151278df5", |
| 133 | + "metadata": {}, |
| 134 | + "outputs": [], |
| 135 | + "source": [ |
| 136 | + "def kahan_variance(data):\n", |
| 137 | + " n = len(data)\n", |
| 138 | + " if n < 2:\n", |
| 139 | + " return float('nan')\n", |
| 140 | + " mean = 0\n", |
| 141 | + " M2 = 0\n", |
| 142 | + " for x in data:\n", |
| 143 | + " y = x - mean\n", |
| 144 | + " t = M2 + y * y - mean * y\n", |
| 145 | + " mean += (y - t) / n\n", |
| 146 | + " M2 = t\n", |
| 147 | + " variance = M2 / (n - 1)\n", |
| 148 | + " return variance" |
| 149 | + ] |
| 150 | + }, |
| 151 | + { |
| 152 | + "cell_type": "code", |
| 153 | + "execution_count": 17, |
| 154 | + "id": "04d20b15-7328-4b86-a321-5ba63a119bfc", |
| 155 | + "metadata": {}, |
| 156 | + "outputs": [], |
| 157 | + "source": [ |
| 158 | + "def neumaier_variance(data):\n", |
| 159 | + " n = len(data)\n", |
| 160 | + " if n < 2:\n", |
| 161 | + " return float('nan')\n", |
| 162 | + " mean = 0\n", |
| 163 | + " M2 = 0\n", |
| 164 | + " for x in data:\n", |
| 165 | + " y = x - mean\n", |
| 166 | + " t = M2 + y * y - mean * y\n", |
| 167 | + " mean += (y - t) / n\n", |
| 168 | + " M2 = t\n", |
| 169 | + " variance = M2 / (n - 1)\n", |
| 170 | + " return variance" |
| 171 | + ] |
| 172 | + }, |
| 173 | + { |
| 174 | + "cell_type": "code", |
| 175 | + "execution_count": 19, |
| 176 | + "id": "b1817c0c-743e-42df-8bef-91409cefc2fa", |
| 177 | + "metadata": {}, |
| 178 | + "outputs": [], |
| 179 | + "source": [ |
| 180 | + "def welford_online(data):\n", |
| 181 | + " n = 0\n", |
| 182 | + " mean = 0\n", |
| 183 | + " M2 = 0\n", |
| 184 | + " for x in data:\n", |
| 185 | + " n += 1\n", |
| 186 | + " delta = x - mean\n", |
| 187 | + " mean += delta / n\n", |
| 188 | + " delta2 = x - mean\n", |
| 189 | + " M2 += delta * delta2\n", |
| 190 | + " if n < 2:\n", |
| 191 | + " return float('nan')\n", |
| 192 | + " variance = M2 / (n - 1)\n", |
| 193 | + " return variance" |
| 194 | + ] |
| 195 | + }, |
| 196 | + { |
| 197 | + "cell_type": "code", |
| 198 | + "execution_count": 21, |
| 199 | + "id": "d2694042-b6dd-4e17-87e4-4ca0c8841ce3", |
| 200 | + "metadata": {}, |
| 201 | + "outputs": [], |
| 202 | + "source": [ |
| 203 | + "def kahan_stable_variance(data):\n", |
| 204 | + " n = len(data)\n", |
| 205 | + " if n < 2:\n", |
| 206 | + " return float('nan')\n", |
| 207 | + " mean = 0\n", |
| 208 | + " M2 = 0\n", |
| 209 | + " for x in data:\n", |
| 210 | + " y = x - mean\n", |
| 211 | + " t = M2 + y * y - mean * y\n", |
| 212 | + " mean += (y - t) / n\n", |
| 213 | + " M2 = t\n", |
| 214 | + " variance = M2 / (n - 1)\n", |
| 215 | + " return variance" |
| 216 | + ] |
| 217 | + }, |
| 218 | + { |
| 219 | + "cell_type": "code", |
| 220 | + "execution_count": 23, |
| 221 | + "id": "afd6a943-7082-476d-b1b5-d582417341da", |
| 222 | + "metadata": {}, |
| 223 | + "outputs": [], |
| 224 | + "source": [ |
| 225 | + "def incremental_compensated_variance(data):\n", |
| 226 | + " n = 0\n", |
| 227 | + " mean = 0\n", |
| 228 | + " M2 = 0\n", |
| 229 | + " for x in data:\n", |
| 230 | + " n += 1\n", |
| 231 | + " delta = x - mean\n", |
| 232 | + " mean += delta / n\n", |
| 233 | + " delta2 = x - mean\n", |
| 234 | + " M2 += delta * delta2\n", |
| 235 | + " if n < 2:\n", |
| 236 | + " return float('nan')\n", |
| 237 | + " variance = M2 / (n - 1)\n", |
| 238 | + " return variance" |
| 239 | + ] |
| 240 | + }, |
| 241 | + { |
| 242 | + "cell_type": "code", |
| 243 | + "execution_count": null, |
| 244 | + "id": "d189d644-c891-43bd-a06d-de0313abb8a0", |
| 245 | + "metadata": {}, |
| 246 | + "outputs": [], |
| 247 | + "source": [] |
| 248 | + }, |
| 249 | + { |
| 250 | + "cell_type": "code", |
| 251 | + "execution_count": null, |
| 252 | + "id": "1af67d1b-b018-4a70-8f0f-6d7e733c57ff", |
| 253 | + "metadata": {}, |
| 254 | + "outputs": [], |
| 255 | + "source": [] |
| 256 | + }, |
| 257 | + { |
| 258 | + "cell_type": "code", |
| 259 | + "execution_count": null, |
| 260 | + "id": "2e11bd17-c3e5-446b-9b94-fefebba2256f", |
| 261 | + "metadata": {}, |
| 262 | + "outputs": [], |
| 263 | + "source": [] |
| 264 | + } |
| 265 | + ], |
| 266 | + "metadata": { |
| 267 | + "kernelspec": { |
| 268 | + "display_name": "Python 3 (ipykernel)", |
| 269 | + "language": "python", |
| 270 | + "name": "python3" |
| 271 | + }, |
| 272 | + "language_info": { |
| 273 | + "codemirror_mode": { |
| 274 | + "name": "ipython", |
| 275 | + "version": 3 |
| 276 | + }, |
| 277 | + "file_extension": ".py", |
| 278 | + "mimetype": "text/x-python", |
| 279 | + "name": "python", |
| 280 | + "nbconvert_exporter": "python", |
| 281 | + "pygments_lexer": "ipython3", |
| 282 | + "version": "3.11.5" |
| 283 | + } |
| 284 | + }, |
| 285 | + "nbformat": 4, |
| 286 | + "nbformat_minor": 5 |
| 287 | +} |
0 commit comments