7.3 The Sampling Distribution of the Sample Mean population:1000:Scale are normally distributed with mean 100 and standard deviation 16 sample:4:可以得到样本均值的分布图如下: 与通过公式计算得到的mean 和 标准差一致:μx¯ = μ = 100 and σx¯ = σ/√n = 16/√4 = 8; 由图可知The histogram is sha…
The Central Limit Theorem (CLT), and the concept of the sampling distribution, are critical for understanding why statistical inference works. There are at least a handful of problems that require you to invoke the Central Limit Theorem on every ASQ…
1. 大数定律(LLN) 设Y1,Y2,……Yn是独立同分布(iid,independently identically distribution)的随机变量,A = SY /n = (Y1+...+Yn)/n.若将Y1,Y2……Yn看做是随机变量Y的n次采样,那么A是Y的采样平均. 因为 ,故 . It is important to understand that the variance of the sum increases with n and the variance of the…
Stat2.2x Probability(概率)课程由加州大学伯克利分校(University of California, Berkeley)于2014年在edX平台讲授. PDF笔记下载(Academia.edu) Summary Standard Error The standard error of a random variable $X$ is defined by $$SE(X)=\sqrt{E((X-E(X))^2)}$$ $SE$ measures the rough size…
title: [概率论]6-3:中心极限定理(The Central Limit Theorem) categories: - Mathematic - Probability keywords: - The Central Limit Theorem - The Normal distribution - The Delta Method toc: true date: 2018-04-09 09:21:44 Abstract: 本文介绍中心极限定理 Keywords: The Central…
大数定律 Law of large numbers (LLN) 虽然名字是 Law,但其实是严格证明过的 Theorem weak law of large number (Khinchin's law) The weak law of large numbers: the sample average converges in probability to the expected value $\bar{X_n}=\frac{1}{n}(X_1+ \cdots +X_n) \overset{…
中心极限定理:每次从总体中抽取容量为n的简单随机样本,这样抽取很多次后,如果样本容量很大,样本均值的抽样分布近似服从正态分布(期望为  ,标准差为 ). (注:总体数据需独立同分布) 那么样本容量n应该达到多大时,才能应用中心极限定理呢?答:对于大多数应用,当样本容量大于等于30时就可以. 从下图中可以看出,不管总体是什么样的分布情况,当样本量达到30的时候,样本均值的抽样分布就是钟形分布了,且样本均值约等于总体均值: 中心极限定理的作用:用样本数据估计总体参数(区间估计). 附: 20世纪初概…
每个大学教材上都会提到这个定理,枯燥地给出了定义和公式,并没有解释来龙去脉,导致大多数人望而生畏,并没有理解它的美. <女士品茶>有感 待续~ 参考:怎样理解和区分中心极限定理与大数定律?…
Inferential Statistics Generalizing from a sample to a population that involves determining how far sample statistics are likely to vary from each other and from the population parameter. Sampling Distribution The sampling distribution of a statistic…
Understanding the Effective Receptive Field in Deep Convolutional Neural Networks 理解深度卷积神经网络中的有效感受野 Abstract摘要 We study characteristics of receptive fields of units in deep convolutional networks. The receptive field size is a crucial issue in many vis…