Update code listings

Listing_11.18.py

@@ -1,15 +1,9 @@
->>> titanic["Age"].notna()
-Name
-Braund, Mr. Owen Harris                                 True
-Cumings, Mrs. John Bradley (Florence Briggs Thayer)     True
-Heikkinen, Miss. Laina                                  True
-Futrelle, Mrs. Jacques Heath (Lily May Peel)            True
-Allen, Mr. William Henry                                True
-                                                       ...
-Montvila, Rev. Juozas                                   True
-Graham, Miss. Margaret Edith                            True
-Johnston, Miss. Catherine Helen "Carrie"               False
-Behr, Mr. Karl Howell                                   True
-Dooley, Mr. Patrick                                     True
-Name: Age, Length: 891, dtype: bool
->>> valid_ages = titanic[titanic["Age"].notna()]
+>>> titanic = pd.read_csv(URL, index_col="Name")
+>>> titanic.head()
+                                                    PassengerId  ...  Embarked
+Name                                                             ...
+Braund, Mr. Owen Harris                                       1  ...         S
+Cumings, Mrs. John Bradley (Florence Briggs Tha...            2  ...         C
+Heikkinen, Miss. Laina                                        3  ...         S
+Futrelle, Mrs. Jacques Heath (Lily May Peel)                  4  ...         S
+Allen, Mr. William Henry                                      5  ...         S

Listing_11.19.py

@@ -1,2 +1,15 @@
-titanic[(titanic["Sex"] == "female") &
-        (titanic["Pclass"] == 3)]["Survived"].mean()
+>>> titanic["Age"].notna()
+Name
+Braund, Mr. Owen Harris                                 True
+Cumings, Mrs. John Bradley (Florence Briggs Thayer)     True
+Heikkinen, Miss. Laina                                  True
+Futrelle, Mrs. Jacques Heath (Lily May Peel)            True
+Allen, Mr. William Henry                                True
+                                                       ...
+Montvila, Rev. Juozas                                   True
+Graham, Miss. Margaret Edith                            True
+Johnston, Miss. Catherine Helen "Carrie"               False
+Behr, Mr. Karl Howell                                   True
+Dooley, Mr. Patrick                                     True
+Name: Age, Length: 891, dtype: bool
+>>> valid_ages = titanic[titanic["Age"].notna()]

Listing_11.20.py

@@ -1,4 +1,2 @@
-male_passengers = titanic[titanic["Sex"] == "male"]
-female_passengers = titanic[titanic["Sex"] == "female"]
-valid_male_ages = male_passengers[titanic["Age"].notna()]
-valid_female_ages = female_passengers[titanic["Age"].notna()]
+titanic[(titanic["Sex"] == "female") &
+        (titanic["Pclass"] == 3)]["Survived"].mean()

Listing_11.21.py

@@ -1 +1,4 @@
->>> from sklearn.linear_model import LinearRegression
+male_passengers = titanic[titanic["Sex"] == "male"]
+female_passengers = titanic[titanic["Sex"] == "female"]
+valid_male_ages = male_passengers[titanic["Age"].notna()]
+valid_female_ages = female_passengers[titanic["Age"].notna()]

Listing_11.22.py

@@ -1,5 +1 @@
-from sklearn.linear_model import LogisticRegression
-from sklearn.naive_bayes import GaussianNB
-from sklearn.linear_model import Perceptron
-from sklearn.tree import DecisionTreeClassifier
-from sklearn.ensemble import RandomForestClassifier
+>>> from sklearn.linear_model import LinearRegression

Listing_11.23.py

@@ -1,7 +1,5 @@
-                        Model
-Score
-0.854749  Decision Tree
-0.854749  Random Forest
-0.787709  Logistic Regression
-0.770950  Naive Bayes
-0.743017  Perceptron
+from sklearn.linear_model import LogisticRegression
+from sklearn.naive_bayes import GaussianNB
+from sklearn.linear_model import Perceptron
+from sklearn.tree import DecisionTreeClassifier
+from sklearn.ensemble import RandomForestClassifier

Listing_11.24.py

@@ -0,0 +1,7 @@
+                        Model
+Score
+0.854749  Decision Tree
+0.854749  Random Forest
+0.787709  Logistic Regression
+0.770950  Naive Bayes
+0.743017  Perceptron