the expression of the amount of doubt that remains after a result is obtained. Althoughuncertainty may be subjective and without foundation (“We are 80% certain that nuclearfusion will be a power source in the 21st century”), many uncertainties are determined bystatistical procedures (“Sampling polls indicate that 63% agree, with a possible3% uncertainty”) ormeasurement uncertainty(e.g., 3.204 &#177 0.005 &#176C).