View Single Post
Old 12-02-2009, 09:59 AM   #185 (permalink)
dippin
Crazy, indeed
 
Location: the ether
Quote:
Originally Posted by GreyWolf View Post
The manipulation of the data to "hide the decline" was done in the base data set. The graph is irrelevant. The explanation later given for the use of the word "trick" smacks of post hoc rationalisation. The entire base data set has been manipulated, and almost certainly appropriately so, in order to try and establish a best-guess homogenous data set. So, the further discussion of replacing selected post-sanitization data points with the express intention of hiding a decline smacks of unethical behaviour. The director of the CRU has stepped aside while an investigation of the whole matter is on-going.

What is more troubling, is that the raw data set (pre-sanitization) is missing... thrown out. This alone makes any review of the current base data set difficult. Again, the rationalisation that it was for space considerations is shaky... microfiche is quite inexpensive, and digitized data can be stored anywhere.

I am not a climatologist, although I have perhaps a slightly more than layman's understanding of the subject. I AM an expert on computer time-series modeling. And climatologists need a modeler to be able to put the data into a format to produce a reasonable forecast. The form of the model significantly affects its predictive qualities and reliability. Univariate, multivariate, regressive, decompositive, dynamic regressive, event models... they all have their strengths, weaknesses, and idiosyncracies.

Deciding which model works best on a given data set is as much the realm of the modeler as it is the subject specialist. I stand by my assertion that I am qualified to comment on the possible effects of the disclosed data manipulation on the predictive quality of the model.

But... that's not been the point of my comments all along. I'm more concerned about the socio/political implications for science research. Scientific research must be about openness and peer review. This reveals systematic violation of that openness, and a predispositon to silence or discredit dissenting views. Healthy debate is good for science. Rejecting criticisms without addressing them, simply because they do not fit your world view, is anathema to proper research.

And I think Ace has hit the nail on the head. If anyone is asking questions that can't be answered, or cause discomfort, then something is wrong. And it's not the people asking the questions.

The fact that you can't even keep straight what is in the emails speaks volumes about your willingness to consider the issue. The email about the "trick" to "hide the decline" is very explicit about this:

Quote:
Once Tim’s got a diagram here we’ll send that either later
today or first thing tomorrow. I’ve just completed Mike’s Nature
trick of adding in the real temps to each series for the last 20
years (ie from 1981 onwards) amd [sic] from1961 for Keith’s to
hide the decline.
He talks about creating a graph from mixing data from two different series, not altering the series themselves.

And the raw dataset was thrown out in the 80s, but ALL the raw data they had is still available. They threw out their own compilation, but the data that went into that compilation is available from the original agencies.

And a forecaster, you should know enough about parameter sensitivity and linearity to know how models differ widely from one another.
dippin is offline  
 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360