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Загрузка данных в DataFrame

In [ ]:
import pandas as pd

df = pd.read_csv("../data/kc_house_data.csv")
In [ ]:
df.head()

Получение сведений о пропущенных данных

In [ ]:
print(df.isnull().sum())
In [ ]:
print(df.isnull().any())
In [3]:
for i in df.columns:
    null_rate = df[i].isnull().sum() / len(df) * 100
    if null_rate > 0:
        print(f"{i} процент пустых значений: {null_rate:.2f}%")

Создание выборок данных

In [9]:
from sklearn.model_selection import train_test_split


def split_stratified_into_train_val_test(
    df_input,
    stratify_colname="y",
    frac_train=0.6,
    frac_val=0.15,
    frac_test=0.25,
    random_state=None,
):
    """
    Splits a Pandas dataframe into three subsets (train, val, and test)
    following fractional ratios provided by the user, where each subset is
    stratified by the values in a specific column (that is, each subset has
    the same relative frequency of the values in the column). It performs this
    splitting by running train_test_split() twice.

    Parameters
    ----------
    df_input : Pandas dataframe
        Input dataframe to be split.
    stratify_colname : str
        The name of the column that will be used for stratification. Usually
        this column would be for the label.
    frac_train : float
    frac_val   : float
    frac_test  : float
        The ratios with which the dataframe will be split into train, val, and
        test data. The values should be expressed as float fractions and should
        sum to 1.0.
    random_state : int, None, or RandomStateInstance
        Value to be passed to train_test_split().

    Returns
    -------
    df_train, df_val, df_test :
        Dataframes containing the three splits.
    """

    if frac_train + frac_val + frac_test != 1.0:
        raise ValueError(
            "fractions %f, %f, %f do not add up to 1.0"
            % (frac_train, frac_val, frac_test)
        )

    if stratify_colname not in df_input.columns:
        raise ValueError("%s is not a column in the dataframe" % (stratify_colname))

    X = df_input  # Contains all columns.
    y = df_input[
        [stratify_colname]
    ]  # Dataframe of just the column on which to stratify.

    # Split original dataframe into train and temp dataframes.
    df_train, df_temp, y_train, y_temp = train_test_split(
        X, y, stratify=y, test_size=(1.0 - frac_train), random_state=random_state
    )

    # Split the temp dataframe into val and test dataframes.
    relative_frac_test = frac_test / (frac_val + frac_test)
    df_val, df_test, y_val, y_test = train_test_split(
        df_temp,
        y_temp,
        stratify=y_temp,
        test_size=relative_frac_test,
        random_state=random_state,
    )

    assert len(df_input) == len(df_train) + len(df_val) + len(df_test)

    return df_train, df_val, df_test
In [15]:
print(df.condition.unique())

data = df[
    [
        "price",
        "bedrooms",
        "bathrooms",
        "sqft_living",
        "sqft_lot",
        "floors",
        "view",
        "condition",
        "grade",
        "sqft_above",
        "sqft_basement",
        "yr_built",
        "yr_renovated",
        "zipcode",
        "lat",
        "long",
    ]
].copy()
[3 5 4 1 2]
In [16]:
df_train, df_val, df_test = split_stratified_into_train_val_test(
    data,
    stratify_colname="condition",
    frac_train=0.60,
    frac_val=0.20,
    frac_test=0.20,
)

print("Обучающая выборка: ", df_train.shape)
print(df_train.condition.value_counts())

print("Контрольная выборка: ", df_val.shape)
print(df_val.condition.value_counts())

print("Тестовая выборка: ", df_test.shape)
print(df_test.condition.value_counts())
Обучающая выборка:  (12967, 16)
condition
3    8418
4    3407
5    1021
2     103
1      18
Name: count, dtype: int64
Контрольная выборка:  (4323, 16)
condition
3    2806
4    1136
5     340
2      35
1       6
Name: count, dtype: int64
Тестовая выборка:  (4323, 16)
condition
3    2807
4    1136
5     340
2      34
1       6
Name: count, dtype: int64
In [18]:
from imblearn.over_sampling import ADASYN

ada = ADASYN()

print("Обучающая выборка: ", df_train.shape)
print(df_train.condition.value_counts())

X_resampled, y_resampled = ada.fit_resample(df_train, df_train["condition"])
df_train_adasyn = pd.DataFrame(X_resampled)

print("Обучающая выборка после oversampling: ", df_train_adasyn.shape)
print(df_train_adasyn.condition.value_counts())
Обучающая выборка:  (12967, 16)
condition
3    8418
4    3407
5    1021
2     103
1      18
Name: count, dtype: int64
Обучающая выборка после oversampling:  (42073, 16)
condition
5    8464
2    8421
1    8420
3    8418
4    8350
Name: count, dtype: int64