Experiments Change the State of Knowledge

The extent of knowledge about 0 can be quantified by showing that probability also can be interpreted as degree of belief (Lindley 1965), measure of plausibility (Loredo 1990), or personal probability (O Hagan 2001). Early workers such as 

Application of Uncertainty Analysis to Ecological Risk of Pesticides 

The above approach, which was attacked as being too vague to be the starting point of any theory of probability, led eventually to the frequentist approach, where probability was defined in a manner that assigns a numerical value, albeit a value that cannot ever be measured, since it requires an inhnite number of trials 

The numerical properties of probability and degrees of belief can be defined effectively and sensibly using a few axioms. 

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