diff --git a/notebook_必备数学基础/假设检验章节/.ipynb_checkpoints/假设检验-checkpoint.ipynb b/notebook_必备数学基础/假设检验章节/.ipynb_checkpoints/假设检验-checkpoint.ipynb
index 18ba4d9..a15d267 100644
--- a/notebook_必备数学基础/假设检验章节/.ipynb_checkpoints/假设检验-checkpoint.ipynb
+++ b/notebook_必备数学基础/假设检验章节/.ipynb_checkpoints/假设检验-checkpoint.ipynb
@@ -34,7 +34,7 @@
    "metadata": {},
    "source": [
     "### 假设校验的基本思想\n",
-    "<img src=\"assets/20201114091803.png\" width=\"50%\">"
+    "<img src=\"assets/20201114091803.png\" width=\"30%\">"
    ]
   },
   {
diff --git a/notebook_必备数学基础/假设检验章节/假设检验.ipynb b/notebook_必备数学基础/假设检验章节/假设检验.ipynb
index 18ba4d9..a15d267 100644
--- a/notebook_必备数学基础/假设检验章节/假设检验.ipynb
+++ b/notebook_必备数学基础/假设检验章节/假设检验.ipynb
@@ -34,7 +34,7 @@
    "metadata": {},
    "source": [
     "### 假设校验的基本思想\n",
-    "<img src=\"assets/20201114091803.png\" width=\"50%\">"
+    "<img src=\"assets/20201114091803.png\" width=\"30%\">"
    ]
   },
   {
diff --git a/notebook_必备数学基础/相关分析/.ipynb_checkpoints/相关分析-checkpoint.ipynb b/notebook_必备数学基础/相关分析/.ipynb_checkpoints/相关分析-checkpoint.ipynb
new file mode 100644
index 0000000..d15e054
--- /dev/null
+++ b/notebook_必备数学基础/相关分析/.ipynb_checkpoints/相关分析-checkpoint.ipynb
@@ -0,0 +1,67 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 相关分析\n",
+    "**相关分析**\n",
+    "<ul>\n",
+    "    <li>衡量事物之间或称变量之间线性相关程度的强弱，并用适当的统计指标表示出来的过程。\n",
+    "    <li>比如，家庭收入和支出、一个人所受教育程度与其收入、子女身高和父母身高等"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "**相关系数**\n",
+    "<ul>\n",
+    "    <li>衡量变量之间相关程度的一个量值。\n",
+    "    <li>相关系数r的数值范围是在-1到+1之间。\n",
+    "    <li>相关系数r的正负号表示变化方向。\"+\"号表示变化方向一致，即正相关:“-”号表示变化方向相反，即负相关。\n",
+    "    <li>r的绝对值表示变量之间的密切程度(即强度)。绝对值越接近1，表示两个变量之间关系越密切；越接近0，表示两个变量之间关系越不密切。\n",
+    "    <li>相关系数的值,仅仅是一个比值。它不是由相等单位度量而来(即不等距)，也不是百分比，因此，不能直接作加、减、乘、除运算。\n",
+    "    <li>相关系数只能描述两个变量之间的变化方向及密切程度,并不能揭示两者之间的内在本质联系,即存在相关的两个变量,不一定存在因果关系。\n",
+    "</ul>\n",
+    "<img src=\"assets/20201119224526.png\" width=\"50%\">"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "左上图是线性相关最低的，右上图是线性相关很明显的；\n",
+    "左下图是线性相关一般的，右下图有一定的相关但不是线性相关；"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.7.3"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}
diff --git a/notebook_必备数学基础/相关分析/assets/20201119224526.png b/notebook_必备数学基础/相关分析/assets/20201119224526.png
new file mode 100644
index 0000000..f348a86
Binary files /dev/null and b/notebook_必备数学基础/相关分析/assets/20201119224526.png differ
diff --git a/notebook_必备数学基础/相关分析/相关分析.ipynb b/notebook_必备数学基础/相关分析/相关分析.ipynb
new file mode 100644
index 0000000..d15e054
--- /dev/null
+++ b/notebook_必备数学基础/相关分析/相关分析.ipynb
@@ -0,0 +1,67 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## 相关分析\n",
+    "**相关分析**\n",
+    "<ul>\n",
+    "    <li>衡量事物之间或称变量之间线性相关程度的强弱，并用适当的统计指标表示出来的过程。\n",
+    "    <li>比如，家庭收入和支出、一个人所受教育程度与其收入、子女身高和父母身高等"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "**相关系数**\n",
+    "<ul>\n",
+    "    <li>衡量变量之间相关程度的一个量值。\n",
+    "    <li>相关系数r的数值范围是在-1到+1之间。\n",
+    "    <li>相关系数r的正负号表示变化方向。\"+\"号表示变化方向一致，即正相关:“-”号表示变化方向相反，即负相关。\n",
+    "    <li>r的绝对值表示变量之间的密切程度(即强度)。绝对值越接近1，表示两个变量之间关系越密切；越接近0，表示两个变量之间关系越不密切。\n",
+    "    <li>相关系数的值,仅仅是一个比值。它不是由相等单位度量而来(即不等距)，也不是百分比，因此，不能直接作加、减、乘、除运算。\n",
+    "    <li>相关系数只能描述两个变量之间的变化方向及密切程度,并不能揭示两者之间的内在本质联系,即存在相关的两个变量,不一定存在因果关系。\n",
+    "</ul>\n",
+    "<img src=\"assets/20201119224526.png\" width=\"50%\">"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "左上图是线性相关最低的，右上图是线性相关很明显的；\n",
+    "左下图是线性相关一般的，右下图有一定的相关但不是线性相关；"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.7.3"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}