为了使用这个公式来计算期望值你需要知道真实的概率值。
In order to compute using this formula you have to know the true probabilities.
事件发生的概率乘以事件的价值，就是该事件的期望值。
You take the probability of the event and multiply it times the value of that event and you have the expected value of that event.
图1：正态概率分布函数，它表明实际的观测值可能会偏离期望值(或者平均值)。
Figure 1: Normal probability density function, which illustrates that actual observations may vary from the expected (or average).
我们把成功的绩效所能导致的一定结果的概率，称为绩效结果期望值。
We assess the probability that successful performance will lead to certain outcomes. The probability is called performance_outcome expectancy.
计算方案的期望损益值区间，利用区间数的排序原理给出概率区间型决策分析的一种新方法。
The paper calculated the expectation increase and decrease value interval of plan, and gave the new method to solve decision making problem under probability interval by interval number principle.
提供了一个在数学期望值不相等条件下进行概率分析的新方法，该方法采用所谓标准差系数作为分析指标。
Using the standard deviation coefficient as analysis target, the author provides a new probability analysis method, in case the mathematical expectations are different.
在加入小概率损失期望值的获益情景中，性别、年龄因素对个体风险决策有显著影响。
Age and gender factors have significant influence on individual risk decision-making, when in the profit situation which is added to loss expectation value of small probability.
在加入小概率获益期望值的损失情景中，年龄和创业倾向对个体风险决策有显著影响。
Age and entrepreneurial intention have significant influence on individual risk decision-making, when in the loss situation which is added to profit expectation value of small probability.
然而，由此求得的设计值，其期望概率远远大于设计标准。
However the design value getting from this method which expectation frequency is larger than the design normal.
将模板支撑架体系的失效概率模糊化，建立了以模糊风险损失期望值最小为依据的风险决策模型。
With the use of fuzzy failure probability, risk decision model based on minimum fuzzy risk loss expectation was presented.
计算数据表明，采用递减转发概率将使得重路由路径长度的期望值显著降低，因而能保证良好的通信延时。
The calculation result demonstrates that descending forward probability makes the expected value of rerouting path decrease distinctly, therefore limits the communication delay.
概率论中另外一个常用的重要的概念是，期望值或者也叫均值，这两个概念可以互换。
Another important concept in probability theory that we will use a lot is expected value, the mean, or average — those are all roughly interchangeable concepts.
对于语者辨识，语者特定模型直接用语者的语料借助于期望值最大化算法（EM）来训练，辨识算法采用了最大事后概率法则（MAP）；
For speaker identification, Expectation Maximization Algorithm (EM) is adopted to train speaker dependent model, and afterwards recognize speaker according to Maximum a Posteriori Criterion (MAP).
证明了在期望值决策准则下，用等概率分层随机抽样得到的方案收益期望值的均值，与用简单随机抽样得到的相同。
It is verified that th action's mean value of the expected value by simple radom sampling is equal to one by stratified radom sampling.
证明了在期望值决策准则下，用等概率分层随机抽样得到的方案收益期望值的均值，与用简单随机抽样得到的相同。
It is verified that th action's mean value of the expected value by simple radom sampling is equal to one by stratified radom sampling.
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