ERHC Energy Inc (ERHE)

[FlightNews]

Risked versus unrisked - I have had the same question and finally and could only find this (and assuming that "conditional" below means unrisked):

http://pubs.usgs.gov/circ/1995/circ1118/resass/term.html

Conditional estimates.-Sizes, numbers, or volumes of oil or natural
gas that are estimated to exist in an area, assuming that they are present.
Conditional estimates, therefore, do not incorporate the risk that the
area may be devoid of oil or natural gas.

Risked (unconditional) estimates.-Resources that are estimated to
exist, including the possibility that the area may be devoid of oil or
natural gas. Statistically, the risked mean may be determined through
multiplication of the mean of a conditional distribution by the related
probability of occurrence. Resource estimates presented in this report
are risked estimates.