Task02：数据分析
1.EDA数据探索性分析
读取文件
import warnings warnings.filterwarnings('ignore') import pandas as pd import numpy as np import matplotlib.pyplot as plt import seaborn as sns import missingno as msno data_train = pd.read_csv('used_car_train_20200313.csv',sep=' ') data_testA = pd.read_csv('used_car_testA_20200313.csv',sep=' ')
2.总览数据概况
理论
1.【总览数据概况】
data.describe() – 统计各个特征的非NaN的个数，均值，标准差，最小值，最大值，分位数。返回dataframe格式的统计表。
data.info() – 统计各个特征的dtype，非NaN的个数等。
2.【判断数据缺失和异常】
data.isnull() – 查看全体数据是否为nan，返回各个位置为nan是True还是False。
data.isnull().sum() – 查看每列（每个特征）存在nan的情况，返回每个特征对应缺失值个数。
data[feature].value_counts() – 统计feature的各个值的个数。
实战
观察数据
data_train.head() SaleID name regDate model brand bodyType fuelType gearbox power kilometer ... v_5 v_6 v_7 v_8 v_9 v_10 v_11 v_12 v_13 v_14 0 0 736 20040402 30.0 6 1.0 0.0 0.0 60 12.5 ... 0.235676 0.101988 0.129549 0.022816 0.097462 -2.881803 2.804097 -2.420821 0.795292 0.914762 1 1 2262 20030301 40.0 1 2.0 0.0 0.0 0 15.0 ... 0.264777 0.121004 0.135731 0.026597 0.020582 -4.900482 2.096338 -1.030483 -1.722674 0.245522 2 2 14874 20040403 115.0 15 1.0 0.0 0.0 163 12.5 ... 0.251410 0.114912 0.165147 0.062173 0.027075 -4.846749 1.803559 1.565330 -0.832687 -0.229963 3 3 71865 19960908 109.0 10 0.0 0.0 1.0 193 15.0 ... 0.274293 0.110300 0.121964 0.033395 0.000000 -4.509599 1.285940 -0.501868 -2.438353 -0.478699 4 4 111080 20120103 110.0 5 1.0 0.0 0.0 68 5.0 ... 0.228036 0.073205 0.091880 0.078819 0.121534 -1.896240 0.910783 0.931110 2.834518 1.923482 5 rows × 31 columns
特征含义
name - 汽车编码
regDate - 汽车注册时间
model - 车型编码
brand - 品牌
bodyType - 车身类型
fuelType - 燃油类型
gearbox - 变速箱
power - 汽车功率
kilometer - 汽车行驶公里
notRepairedDamage - 汽车有尚未修复的损坏
regionCode - 看车地区编码
seller - 销售方
offerType - 报价类型
creatDate - 广告发布时间
price - 汽车价格
v_0’, ‘v_1’, ‘v_2’, ‘v_3’, ‘v_4’, ‘v_5’, ‘v_6’, ‘v_7’, ‘v_8’, ‘v_9’, ‘v_10’, ‘v_11’, ‘v_12’, ‘v_13’,‘v_14’（根据汽车的评论、标签等大量信息得到的embedding向量）【人工构造 匿名特征】
详细信息
data_train.describe() SaleID name regDate model brand bodyType fuelType gearbox power kilometer ... v_5 v_6 v_7 v_8 v_9 v_10 v_11 v_12 v_13 v_14 count 150000.000000 150000.000000 1.500000e+05 149999.000000 150000.000000 145494.000000 141320.000000 144019.000000 150000.000000 150000.000000 ... 150000.000000 150000.000000 150000.000000 150000.000000 150000.000000 150000.000000 150000.000000 150000.000000 150000.000000 150000.000000 mean 74999.500000 68349.172873 2.003417e+07 47.129021 8.052733 1.792369 0.375842 0.224943 119.316547 12.597160 ... 0.248204 0.044923 0.124692 0.058144 0.061996 -0.001000 0.009035 0.004813 0.000313 -0.000688 std 43301.414527 61103.875095 5.364988e+04 49.536040 7.864956 1.760640 0.548677 0.417546 177.168419 3.919576 ... 0.045804 0.051743 0.201410 0.029186 0.035692 3.772386 3.286071 2.517478 1.288988 1.038685 min 0.000000 0.000000 1.991000e+07 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.500000 ... 0.000000 0.000000 0.000000 0.000000 0.000000 -9.168192 -5.558207 -9.639552 -4.153899 -6.546556 25% 37499.750000 11156.000000 1.999091e+07 10.000000 1.000000 0.000000 0.000000 0.000000 75.000000 12.500000 ... 0.243615 0.000038 0.062474 0.035334 0.033930 -3.722303 -1.951543 -1.871846 -1.057789 -0.437034 50% 74999.500000 51638.000000 2.003091e+07 30.000000 6.000000 1.000000 0.000000 0.000000 110.000000 15.000000 ... 0.257798 0.000812 0.095866 0.057014 0.058484 1.624076 -0.358053 -0.130753 -0.036245 0.141246 75% 112499.250000 118841.250000 2.007111e+07 66.000000 13.000000 3.000000 1.000000 0.000000 150.000000 15.000000 ... 0.265297 0.102009 0.125243 0.079382 0.087491 2.844357 1.255022 1.776933 0.942813 0.680378 max 149999.000000 196812.000000 2.015121e+07 247.000000 39.000000 7.000000 6.000000 1.000000 19312.000000 15.000000 ... 0.291838 0.151420 1.404936 0.160791 0.222787 12.357011 18.819042 13.847792 11.147669 8.658418 8 rows × 30 columns print(data_train.shape,data_testA.shape) (150000, 31) (50000, 30)
查看缺失值
print(data_train.isnull().sum()) print(data_testA.isnull().sum()) SaleID 0 name 0 regDate 0 model 1 brand 0 bodyType 4506 fuelType 8680 gearbox 5981 power 0 kilometer 0 notRepairedDamage 0 regionCode 0 seller 0 offerType 0 creatDate 0 price 0 v_0 0 v_1 0 v_2 0 v_3 0 v_4 0 v_5 0 v_6 0 v_7 0 v_8 0 v_9 0 v_10 0 v_11 0 v_12 0 v_13 0 v_14 0 dtype: int64 SaleID 0 name 0 regDate 0 model 0 brand 0 bodyType 1413 fuelType 2893 gearbox 1910 power 0 kilometer 0 notRepairedDamage 0 regionCode 0 seller 0 offerType 0 creatDate 0 v_0 0 v_1 0 v_2 0 v_3 0 v_4 0 v_5 0 v_6 0 v_7 0 v_8 0 v_9 0 v_10 0 v_11 0 v_12 0 v_13 0 v_14 0 dtype: int64
从统计情况看，训练数据中model、bodyType、fuelType、gearbox存在缺失值
查看是否有异常值
print(Train_data.info())
结果如下：
<class 'pandas.core.frame.DataFrame'> RangeIndex: 150000 entries, 0 to 149999 Data columns (total 31 columns): # Column Non-Null Count Dtype --- ------ -------------- ----- 0 SaleID 150000 non-null int64 1 name 150000 non-null int64 2 regDate 150000 non-null int64 3 model 149999 non-null float64 4 brand 150000 non-null int64 5 bodyType 145494 non-null float64 6 fuelType 141320 non-null float64 7 gearbox 144019 non-null float64 8 power 150000 non-null int64 9 kilometer 150000 non-null float64 10 notRepairedDamage 150000 non-null object 11 regionCode 150000 non-null int64 12 seller 150000 non-null int64 13 offerType 150000 non-null int64 14 creatDate 150000 non-null int64 15 price 150000 non-null int64 16 v_0 150000 non-null float64 17 v_1 150000 non-null float64 18 v_2 150000 non-null float64 19 v_3 150000 non-null float64 20 v_4 150000 non-null float64 21 v_5 150000 non-null float64 22 v_6 150000 non-null float64 23 v_7 150000 non-null float64 24 v_8 150000 non-null float64 25 v_9 150000 non-null float64 26 v_10 150000 non-null float64 27 v_11 150000 non-null float64 28 v_12 150000 non-null float64 29 v_13 150000 non-null float64 30 v_14 150000 non-null float64 dtypes: float64(20), int64(10), object(1)
代码示例
载入各种数据科学以及可视化库
载入数据
总览数据概况
判断数据缺失和异常
了解预测值的分布
特征分为类别特征和数字特征，并对类别特征查看unique分布
数字特征分析
类别特征分析
用pandas_profiling生成数据报告
