# normal approximation definition

In some cases, working out a problem using the Normal distribution may be easier than using a Binomial. More about the Poisson distribution probability so you can better use the Poisson calculator above: The Poisson probability is a type of discrete probability distribution that can take random values on the range $$[0, +\infty)$$.. Its familiar bell-shaped curve is ubiquitous in statistical reports, from survey analysis and quality control to resource allocation. That translates to  P(\mbox{Number of Defects } ... CallUrl('www>itl>nist>govhtm',1), The ~TildeLink() simplifies the calculations. The use of normal approximation makes this task quite easy. The normal distribution can be used as an approximation to the binomial distribution, under certain circumstances, namely: If X ~ B (n, p) and if n is large and/or p is close to ½, then X is approximately N (np, npq) (where q = 1 - p). This approximates the binomial probability (with continuity correction) … There also exist other, higher order, ~TildeLink()s of the binomial distribution.If the number of independent trials is large, while the probability is small, the individual probabilities can be approximately expressed in terms of the Poisson distribution: ... CallUrl('www>encyclopediaofmath>orgphpstatmethods>nethtml',1), means[i] = mean(boot.sample) + } quantile(boot.means, c(.025,.975)) 2.5% 97.5% 28.71027 31.37937 The bootstrapped CI is reasonably close to the one obtained by traditional methods, so the ~TildeLink() seems to be reasonable for these data. Figure 1 – Hypothesis testing for Kendall’s tau using normal approximation Since p-value = .006 < .05 = α (two-tail test), the null hypothesis is rejected (that smoking and longevity are independent), and so we conclude there is a negative correlation between smoking and longevity. If n is large enough, then the skew of the distribution is not too great. CallUrl('ww2>coastal>eduhtml',0). The normal distribution is used as an approximation for the Binomial Distribution when X ~ B (n, p) and if 'n' is large and/or p is close to ½, then X is approximately N (np, npq). The normal approximation is accurate for large sample sizes and for proportions between 0.2 and 0.8, roughly. If the distribution of can be approximated by a normal distribution with mean and variance , the quantile premium is given by the formula(18.34) ... CallUrl('sfb649>wiwi>hu-berlin>dehtml',0), Theorem: ~TildeLink() to the Binomial DistributionIf a binomial distribution with probability of success p and failure q and n trials is such thatnp 5 ... CallUrl('ltcconline>nethtm',0), Section 5.6 ~TildeLink()s to Binomial Distributions (p 251)The Central Limit Theorem can be restated to apply to the sum of sample measurements as follows:is normally distributed with mean = and standard deviation = as n becomes large. Using this property is the normal approximation to the binomial distribution. Normal Approximation to the Binomial Some variables are continuous—there is no limit to the number of times you could divide their intervals into still smaller ones, although you may round them off for convenience.