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Using NumPy

After install NumPy, import it as a library:

import numpy as np

Creating NumPy Arrays

From a Python List

my_list = [1,2,3]
np.array(my_list)

my_matrix = [[1,2,3],[4,5,6],[7,8,9]]
np.array(my_matrix)
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Anaconda: a distribution of Python
Jupyter: a development environment (IDE) where we can write code, display images, and write markdown notes.

Open Jupyter Notebook

  1. Anaconda Navigator -> Jupyter Notebook
    By this way, we can only open Jupyter Notebook for data under C:\User\User\ (the layer of Anaconda3 is)

  2. Anaconda prompt -> change directory to where *.ipynb files are -> ‘$ Jupyter Notebook’

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Q9: Consider a bin with infinitely many marbles, and let μ be the fraction of orange marbles in the bin, and ν is the fraction of orange marbles in a sample of 10 marbles. If μ=0.5, what is the probability of ν=μ? Please choose the closest number.

Explanation

u是罐子中的黄色小球概率，v是样本中的黄色小球概率，u=0.5。题目中已规定v=u=0.5，则10个样本中黄色球的个数为10*v=5，剩下的绿色球的个数为10-5=5。

最后实际上是要求解：取出来的10个样本中，黄色小球为5个 绿色小球为5个的概率。

注意，要用v来计算样本中各类小球的数量，这仅仅代表取样结果。真实取样时，要用罐子中的实际概u来求解。）

Ref:Class Forum

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