Table 2 below shows the preliminary consensus values for each sample and also by the three different laboratory types. These results show evidence of a significant age difference between the laboratory types, with the LSC results , on average, being younger. The results for each sample were then further analysed to explore whether there was a significant difference in the average age for the different laboratory types, or due to the modern standard or to the background material. Table 4 below shows for which samples statistically significant differences were found. The preliminary consensus values are very close to the master 14 C ages, estimated from the calibration data.
Duplicates allow an independent estimate of laboratory repeatability.
The summary of the pair-wise differences is shown in table 6 below. The average difference in the duplicates is very small, and well within the standard error, implying good agreement. These analyses were presented and discussed in some detail at the workshop and a list of further analyses drawn up. In particular, analysis and summarisation of the d 13 C results, a sensitivity analysis of different approaches to calculation of consensus values and a consideration of the associated errors were identified. In addition, indicators of individual laboratory performance would be computed and summarised.