## The Normal Approximation to the Geometric Distribution - The Continuity Correction

The geometric distribution, written hasExpectation Value Thevariance is given by Ifwe want to use the normal distribution as an approximation toestimate forexample we must make modifications since the binomial distribution isa discrete distribution but the normal approximation is continuous.

In order to take account of this, and that if we areestimating maybe equal to 80, when we use the normal approximation Suppose Thenormal approximation is  Look up the probability corresponding to andsubtract from 1. This returns a probability of 0.0244. maybe equal to 110, when we use the normal approximation As above Thenormal approximation is  Look up the probability corresponding to Thisreturns a probability of 0.8315. To find wesubtract from 1 to obtain 0.1685. maybe not be equal to 120. When we use the normal approximation As above Thenormal approximation is  Look up the probability corresponding to Thisreturns a probability of 0.9808. We subtract this from 1 to obtain0.0192. maynot be equal to 114, when we use the normal approximation Asabove Thenormal approximation is  Look up the probability corresponding to This returns a probability of 0.8962. 