edit done I posted this here in an attempt to follow the rules for independent study. My knowledge of statistics is very rudimentary, so I would like to know if my approach does make any sense of not. 1. The problem statement, all variables and given/known data The question is determine the age of a certain event based on a series of binominal/normal distibuted datasets, all looking for the same event age but with different methods. Record 1 is given as counted 10 times by different people leading to an average of 13200 years with σ= 20 Record 2 is given as counted as 12985 certain years with 150 uncertain layers that may or may not be years. So the authors split the difference and conclude: 13260 years with an absolute error of 75 years Record 3 is reported as 13215 counted years with a 1% error Record 4 is calculated etc giving a result of 13195 years with σ=35 So what would be a realistic average value with realistic σ? 2. Relevant equations Normal distribution.- 3. The attempt at a solution I wondered if it would work if I treated all record sets as normal distributions and then multiply all four of them for each data point. To get σ's for records 2 and 3 I used the absolute error as the 3σ range, getting values of 25 and 44 years respectively. Then I created this spreadsheet, using 5 year intervals, which is ample in the branch. https://dl.dropboxusercontent.com/u/22026080/numbers-crunching.xlsx [Broken] I just multiplied all data in the series of the four records (column I) and then corrected it to get a sum of 1 under the graph (column F). Colums J-K-L are just a help to find the average and σ which turns out to be 13220 ± 20. [Broken] Does this make sense? The result is close to the 2σ boundary with record 2. Therefore I made a refinement tool (column G) to find the least squares (manual - trial and error) which turned out to be 13218 ± 14(?) years. Does that make sense too, since I'm working with 5 year intervals? Finally, does it make sense to mail the author of record 2 telling him that his method of splitting the difference between certain and uncertain years makes his result an outlier?