 In principle, there are many ways that one can go about aggregating credences or pooling opinions (Genest and Zidek 1986). A simple option is to combine opinions by linear pooling—taking a weighted average of credences. This averaging could respect all credences equally, or put extra weights on the opinions of, say, recognized experts. This option has some nice properties, such as preserving unanimous agreement, and allowing groups to aggregate over different topics independently (DeGroot 1974; Lehrer and Wagner  1981).[1]