问题如下图：
选项：
A. 
B. 
C. 
D. 
解释：
看了以前的提问，还是不懂，求详细一步步分析。
确实FRM没有CFA讲的好，一脸懵逼，怎么办。
orange品职答疑助手 · 2019年08月18日
个人认为这里的成功率，说的不是二项分布里的那个p，而是泊松分布里的那个λ.
泊松分布的参数λ是单位时间(或单位面积)内随机事件的平均发生率，它等于n*p。当n足够大时，泊松分布就可以用正态分布来近似，而此时，λ也因为n的增大而增大，最终趋向于它的最大值也就是1。
这道题是2004年前的真题了。但我们现在一般都不这样说了。我记得之前学概率论的时候，只是强调泊松分布中，λ=np的n足够大，就可以由中心极限定理趋近于正态分布。这道题有个印象就好，万一真的考到。
FRM比CFA更偏数理逻辑一些，而且它考察的较为广泛。不过FRM通过是比CFA简单的。
NO.PZ2016062402000016 When cyou use the normstribution to approximate the Poisson stribution, assuming you have n inpennt trials, eawith a probability of success of p? When the meof the Poisson stribution is very small When the varianof the Poisson stribution is very small When the number of observations is very large anthe success rate is close to 1 When the number of observations is very large anthe success rate is close to 0 The normapproximation to the Poisson improves when the success rate, χ, is very high. Because this is also the meanvariance, answers A anare wrong. In turn, the binominsity is well approximatethe Poisson nsity when np = χ is large. 辅导员，这里也是没明白为啥要接近于1，数据的规模这个是没有问题
When cyou use the normstribution to approximate the Poisson stribution, assuming you have n inpennt trials, eawith a probability of success of p? When the meof the Poisson stribution is very small When the varianof the Poisson stribution is very small When the number of observations is very large anthe success rate is close to 1 When the number of observations is very large anthe success rate is close to 0 The normapproximation to the Poisson improves when the success rate, χ, is very high. Because this is also the meanvariance, answers A anare wrong. In turn, the binominsity is well approximatethe Poisson nsity when np = χ is large. 请问这个success rate为什么要接近1呢 不是np越大就可以越好的approximate么
When cyou use the normstribution to approximate the Poisson stribution, assuming you have n inpennt trials, eawith a probability of success of p? When the meof the Poisson stribution is very small When the varianof the Poisson stribution is very small When the number of observations is very large anthe success rate is close to 1 When the number of observations is very large anthe success rate is close to 0 The normapproximation to the Poisson improves when the success rate, χ, is very high. Because this is also the meanvariance, answers A anare wrong. In turn, the binominsity is well approximatethe Poisson nsity when np = χ is large. P->0, 为什么不选
When cyou use the normstribution to approximate the Poisson stribution, assuming you have n inpennt trials, eawith a probability of success of p? When the meof the Poisson stribution is very small When the varianof the Poisson stribution is very small When the number of observations is very large anthe success rate is close to 1 When the number of observations is very large anthe success rate is close to 0 The normapproximation to the Poisson improves when the success rate, χ, is very high. Because this is also the meanvariance, answers A anare wrong. In turn, the binominsity is well approximatethe Poisson nsity when np = χ is large. 为啥不选possion分布的适用条件不是概率很小，N很大吗？老师讲的
P不可能大，所以np很大的实质就是n很大对吧？