所以任务持续时间不是一个单一的实数，而是描述一定时间范围内完成的可能性的随机变量。

So the task duration is not a single real number, rather it is a random variable that describes the likelihood of completion within a certain range of time.

youdao

取代单个值，随机变量拥有描述估计值可能性的函数，该函数称为变量的概率分布。

Instead of this single value, a random variable has a function that describes the likelihood of values for the estimate and is called the variable's probability distribution.

youdao

显然，一个结构上的不同是我们的网络有20个输入节点，但这是很正常的，因为我们的描述已经暗示了这种可能性。

Clearly, one structural difference is that our net has twenty input nodes, but this should not be surprising, since our description has already suggested this possibility.

youdao

The idea is that probability measures the likelihood of some outcome.

概率是用来描述,某一结果发生的可能性

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