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1、exciting spirit, to , not up of urgency, and slow shall not of sense, and sat not of sense, moments has a lying sake thing, and sat with rules of procedure of the, and station with officer of momentum, keep a ran of drive, and Rob of consciousness, and race of momentum, and spell of courage, to fire
2、 as of passion input work. The only way to ensure the healthy development of the cause, did not live up to the Organizations trust and the porcelain people live up to expectations. (B) the practice of three Suns, requires that we adhere to the problem oriented, improving the effectiveness of Governm
3、ent. An idea that I have said many times, talking about issues is much more useful than the talk. Because the results are in the past, talking about there, but the problem is eternal, not free, ubiquitous, if not resolved, will never go away on their own, and then only by solving a problem, work in
4、order to move forward, before moving forward progress of society. Marxist philosophy tells us that catch to catch the nature of the problem, grab the contradiction to catch the main contradiction. This requires us not only to be good at resolving individual, specific issues, also to be good at looki
5、ng through the phenomenon of nature, found by accident law, so as to catch common, widespread problem. We some place and sector of comrade, work starting point is good of, wants to developed some policy, wants to help enterprise development, and for masses do points things, but is careless make a kn
6、ife cut pot, upper and lower general rough, led to file introduced Hou hard implementation, some even help has pour busy, to enterprise increased has burden, damage has masses of interests; some place in do city development planning or industry development planning Shi, to self for Center, pursuit w
7、ishful thinking, not focused on and city general planning phase convergence, Final conflict for planning land cannot be submitted for approval, the project cant fall, wasted time, energy and money. In addition, there are many comrades often complain about difficult, superiors know the problem instea
8、d of trying, often report to prepare funding conditions. In fact, if any conditions are prepared properly, who called that is not the same?, conversely, if you are really looking for the right reasons, there is a good solution, the Government will provide support in terms of manpower, material and f
9、inancial resources. Government agencies set is a science, departments does the difference between good and bad, the difference only work well. Can get the attention and support, the key achievements and contributions to the Department. We carry out Government work, do anything to stick to problem-or
10、iented, be sure to have clear links to, take practical measures to achieve real results. This requires that we must reach out before the decision, . Help, in order to help companies ride out the storm. Last month, the City Government carried out a steady growth and development of research, many comr
11、ades told me that, in the course of land, some farmers dont understand municipal government decisions, even plain, block construction. On this issue, we should not only see the appearance of land expropriation, but on the other hand, thought the masses why conflict? worried that without a job, there
12、 are still other worries? can then take specific measures to resolve it. For example, baic Changhe automobile new bases in the land acquisition process and for surrounding farmers making a special people Club sector statistics, finds out, and organizations develop the skills training, Government 正态分
13、布及其应用一、 正态分布的概念和特征根据频数表资料绘制成直方图,可以设想,如果将观察人数逐渐增多,线段不断分细,图中直条将逐渐变窄,其顶端将逐渐接近一条光滑的曲线,这条曲线称为频数曲线或频率曲线,略呈钟型,两头低,中间高,左右对称,近似于数学上的正态分布(normal distribution)。由于频率的总和等于100%或1,故横轴上曲线下的面积等于100%或1。 正态分布是一种横重要的连续型分布,在生物统计学中,占有极其重要的地位。许多生物学现象所产生的数据,都服从正态分布。 1、正态分布的图形 有了正态分布的密度函数f(X),即正态分布的方程,就可给出图形 -s m s 上式中右側m为均
14、数,s为标准差,X为自变量。当X确定后,就可由此式求得其密度函数f(X),也就是相应的纵坐标的高度。所以,已知m和 s , 就能绘出正态曲线的图形。2、正态分布的特征(1) 正态分布以m为中心,左右对称。(2)正态分布有两个参数,即m和s。m是位置参数,当s恒定后,m 越大,则曲线沿横轴越向右移动;m 越小,则曲线沿横轴越向左移动。s是变异参数,当m 恒定时,s越大,表示数据越分散,曲线越“胖”;s越小,表示数据越分散,曲线越“瘦”。(3)正态分布的偏斜度 g1=0,峭度 g2=0为了应用方便,常将上式作如下变换, 也就是将原点移到 m 的位置,使横轴尺度以s为单位,使m=0,s=1,则正态分
15、布变换为标准正态分布。(standard normal distribution) ,u称为标准正态离差(standard normal deviate)标准正态分布的密度函数为: 一般用N(m,s2)表示均方为m,方差为s2的正态分布。于是标准正态分布用N(0,1)表示。 -3 -2 -1 0 1 2 3 68.26% 95.45% 99.74%下列一些值很重要,应予记忆:u= -1 到 u=1 面积=0.6827u= -1.96 到 u=1.96 面积=0.9500u= -2.58 到 u=2.58 面积=0.9900标准正态分布有以下特征:(1) 在u=0时,j(u)达到最大值。(2) 当u无论向哪个方向远离0时,j(u)的值都减小。(3) 曲线关于Y轴对称,即j(u)=j(-u)。(4) 曲线和横轴所夹的面积等于1。二、标准正态曲线下面积的计算 P(u1 U u2) =j(u2) - j(u1)举例已知高梁品种“三尺三