diff --git a/source/index.rst b/source/index.rst
index b798d5f..5bf2380 100644
--- a/source/index.rst
+++ b/source/index.rst
@@ -10,6 +10,7 @@ Welcome to ScienceNotes's documentation!
    :maxdepth: 2
    :caption: Contents:
 
+   statistics/index
 
 
 Indices and tables
diff --git a/source/statistics/index.rst b/source/statistics/index.rst
new file mode 100644
index 0000000..08bcb9f
--- /dev/null
+++ b/source/statistics/index.rst
@@ -0,0 +1,11 @@
+Statistics
+=========================
+
+.. toctree::
+   :maxdepth: 2
+
+   self
+   introduction
+
+dlkdd
+sd
diff --git a/source/statistics/introduction.rst b/source/statistics/introduction.rst
new file mode 100644
index 0000000..28fb145
--- /dev/null
+++ b/source/statistics/introduction.rst
@@ -0,0 +1,4 @@
+Introduction
+==================
+
+dd