RE:Chance of Commerciality 51 percent Read closely
It is important to read the footnotes of the resource assessment news release for the "best estimate" and "Mean estimate" which clearly state that the meaning. The mean estimate is the expected value and the most representative.
Best Estimate (7.3 TCF)
(3) The best estimate is the P50 quantity. P50 means there is a 50% chance that the estimated quantity will be equaled or exceeded.
Mean Estimate (10.1 TCF)
(5) The mean estimate is the probability-weighted average (expected value).
Read more at https://www.stockhouse.com/news/press-releases/2018/02/06/valeura-announces-prospective-resources-for-unconventional-basin-centered-gas#gC55zJasbrt1kDKD.99