#TITLE: Mode hunting #DESCRIPTION: Data from proficiency tests, used in published demonstration of mode-hunting with the EM algorithm. #VARIABLES: Concentrations of: PUFA=polyunsaturated fatty acids, nickel, tin #UNITS: PUFA; mass fraction times 10^2 (% by mass) #UNITS: Nickel; mass fraction times 10^6 (ppm) #UNITS: Tin; mass fraction times 10^6 #REFERENCE_VALUES: Tin only; by ICP-IDMS; 286.5 (U=3.5) #APPLICATION_SECTOR: Food, geology #ANALYTE: PUFA, Ni, Sn #MATRIX_TYPE: PUFA; Fat spread: Sn; tomato paste: Ni; volcanic glass #RATIONALE: Proficiency testing #DATA_TYPE: Experimental #DATA_STRUCTURE: Simple #CONDITIONS: Reproducibility #ORIGIN: FAPAS, GeoPT #DATE_OF_ORIGIN: 2006 #AUTHOR: M Thompson #AUTHOR_ADDRESS: Birkbeck College, Malet Street, London WC1E 7HX. #LITERATURE_REFERENCES: Accred Qual Assur 2006, 10, 501-505. PUFA Tin Nickel 40.7 203 143 39 218 319 40.8 220 320 38.633 226 282 39 228 255 40.9 233 170 39.3 242 317.717 39.6 243 294.132 39.4 243.7 330.5 39.1 244 242.626 39.9 246 300 39.1 247 316.25 40.079 247.162 334.5 39.4 247.95 300.733 40.7 248 316 40.2 251 211.952 40.75 252 165.25 38.835 255 329.213 39.8 256 175 38.6 260 40 263 40.3 265 39.22 265 39.04 266 39.3 272 40.5 272 39.5 273.79 40.7 277 39.3 279 39.2 279.3 39.5 280 41.132 280 38.9 281 40.43 284 39.3 285 39.5 290.2 39.1 296 39.6 39.44 40.5 39.8 41