阈值分类法

数据集:seeds.tsv

15.26    14.84    0.871    5.763    3.312    2.221    5.22    Kama
14.88    14.57    0.8811    5.554    3.333    1.018    4.956    Kama
14.29    14.09    0.905    5.291    3.337    2.699    4.825    Kama
13.84    13.94    0.8955    5.324    3.379    2.259    4.805    Kama
16.14    14.99    0.9034    5.658    3.562    1.355    5.175    Kama
14.38    14.21    0.8951    5.386    3.312    2.462    4.956    Kama
14.69    14.49    0.8799    5.563    3.259    3.586    5.219    Kama
14.11    14.1    0.8911    5.42    3.302    2.7    5.0    Kama
16.63    15.46    0.8747    6.053    3.465    2.04    5.877    Kama
16.44    15.25    0.888    5.884    3.505    1.969    5.533    Kama
15.26    14.85    0.8696    5.714    3.242    4.543    5.314    Kama
14.03    14.16    0.8796    5.438    3.201    1.717    5.001    Kama
13.89    14.02    0.888    5.439    3.199    3.986    4.738    Kama
13.78    14.06    0.8759    5.479    3.156    3.136    4.872    Kama
13.74    14.05    0.8744    5.482    3.114    2.932    4.825    Kama
14.59    14.28    0.8993    5.351    3.333    4.185    4.781    Kama
13.99    13.83    0.9183    5.119    3.383    5.234    4.781    Kama
15.69    14.75    0.9058    5.527    3.514    1.599    5.046    Kama
14.7    14.21    0.9153    5.205    3.466    1.767    4.649    Kama
12.72    13.57    0.8686    5.226    3.049    4.102    4.914    Kama
14.16    14.4    0.8584    5.658    3.129    3.072    5.176    Kama
14.11    14.26    0.8722    5.52    3.168    2.688    5.219    Kama
15.88    14.9    0.8988    5.618    3.507    0.7651    5.091    Kama
12.08    13.23    0.8664    5.099    2.936    1.415    4.961    Kama
15.01    14.76    0.8657    5.789    3.245    1.791    5.001    Kama
16.19    15.16    0.8849    5.833    3.421    0.903    5.307    Kama
13.02    13.76    0.8641    5.395    3.026    3.373    4.825    Kama
12.74    13.67    0.8564    5.395    2.956    2.504    4.869    Kama
14.11    14.18    0.882    5.541    3.221    2.754    5.038    Kama
13.45    14.02    0.8604    5.516    3.065    3.531    5.097    Kama
13.16    13.82    0.8662    5.454    2.975    0.8551    5.056    Kama
15.49    14.94    0.8724    5.757    3.371    3.412    5.228    Kama
14.09    14.41    0.8529    5.717    3.186    3.92    5.299    Kama
13.94    14.17    0.8728    5.585    3.15    2.124    5.012    Kama
15.05    14.68    0.8779    5.712    3.328    2.129    5.36    Kama
16.12    15.0    0.9    5.709    3.485    2.27    5.443    Kama
16.2    15.27    0.8734    5.826    3.464    2.823    5.527    Kama
17.08    15.38    0.9079    5.832    3.683    2.956    5.484    Kama
14.8    14.52    0.8823    5.656    3.288    3.112    5.309    Kama
14.28    14.17    0.8944    5.397    3.298    6.685    5.001    Kama
13.54    13.85    0.8871    5.348    3.156    2.587    5.178    Kama
13.5    13.85    0.8852    5.351    3.158    2.249    5.176    Kama
13.16    13.55    0.9009    5.138    3.201    2.461    4.783    Kama
15.5    14.86    0.882    5.877    3.396    4.711    5.528    Kama
15.11    14.54    0.8986    5.579    3.462    3.128    5.18    Kama
13.8    14.04    0.8794    5.376    3.155    1.56    4.961    Kama
15.36    14.76    0.8861    5.701    3.393    1.367    5.132    Kama
14.99    14.56    0.8883    5.57    3.377    2.958    5.175    Kama
14.79    14.52    0.8819    5.545    3.291    2.704    5.111    Kama
14.86    14.67    0.8676    5.678    3.258    2.129    5.351    Kama
14.43    14.4    0.8751    5.585    3.272    3.975    5.144    Kama
15.78    14.91    0.8923    5.674    3.434    5.593    5.136    Kama
14.49    14.61    0.8538    5.715    3.113    4.116    5.396    Kama
14.33    14.28    0.8831    5.504    3.199    3.328    5.224    Kama
14.52    14.6    0.8557    5.741    3.113    1.481    5.487    Kama
15.03    14.77    0.8658    5.702    3.212    1.933    5.439    Kama
14.46    14.35    0.8818    5.388    3.377    2.802    5.044    Kama
14.92    14.43    0.9006    5.384    3.412    1.142    5.088    Kama
15.38    14.77    0.8857    5.662    3.419    1.999    5.222    Kama
12.11    13.47    0.8392    5.159    3.032    1.502    4.519    Kama
11.42    12.86    0.8683    5.008    2.85    2.7    4.607    Kama
11.23    12.63    0.884    4.902    2.879    2.269    4.703    Kama
12.36    13.19    0.8923    5.076    3.042    3.22    4.605    Kama
13.22    13.84    0.868    5.395    3.07    4.157    5.088    Kama
12.78    13.57    0.8716    5.262    3.026    1.176    4.782    Kama
12.88    13.5    0.8879    5.139    3.119    2.352    4.607    Kama
14.34    14.37    0.8726    5.63    3.19    1.313    5.15    Kama
14.01    14.29    0.8625    5.609    3.158    2.217    5.132    Kama
14.37    14.39    0.8726    5.569    3.153    1.464    5.3    Kama
12.73    13.75    0.8458    5.412    2.882    3.533    5.067    Kama
17.63    15.98    0.8673    6.191    3.561    4.076    6.06    Rosa
16.84    15.67    0.8623    5.998    3.484    4.675    5.877    Rosa
17.26    15.73    0.8763    5.978    3.594    4.539    5.791    Rosa
19.11    16.26    0.9081    6.154    3.93    2.936    6.079    Rosa
16.82    15.51    0.8786    6.017    3.486    4.004    5.841    Rosa
16.77    15.62    0.8638    5.927    3.438    4.92    5.795    Rosa
17.32    15.91    0.8599    6.064    3.403    3.824    5.922    Rosa
20.71    17.23    0.8763    6.579    3.814    4.451    6.451    Rosa
18.94    16.49    0.875    6.445    3.639    5.064    6.362    Rosa
17.12    15.55    0.8892    5.85    3.566    2.858    5.746    Rosa
16.53    15.34    0.8823    5.875    3.467    5.532    5.88    Rosa
18.72    16.19    0.8977    6.006    3.857    5.324    5.879    Rosa
20.2    16.89    0.8894    6.285    3.864    5.173    6.187    Rosa
19.57    16.74    0.8779    6.384    3.772    1.472    6.273    Rosa
19.51    16.71    0.878    6.366    3.801    2.962    6.185    Rosa
18.27    16.09    0.887    6.173    3.651    2.443    6.197    Rosa
18.88    16.26    0.8969    6.084    3.764    1.649    6.109    Rosa
18.98    16.66    0.859    6.549    3.67    3.691    6.498    Rosa
21.18    17.21    0.8989    6.573    4.033    5.78    6.231    Rosa
20.88    17.05    0.9031    6.45    4.032    5.016    6.321    Rosa
20.1    16.99    0.8746    6.581    3.785    1.955    6.449    Rosa
18.76    16.2    0.8984    6.172    3.796    3.12    6.053    Rosa
18.81    16.29    0.8906    6.272    3.693    3.237    6.053    Rosa
18.59    16.05    0.9066    6.037    3.86    6.001    5.877    Rosa
18.36    16.52    0.8452    6.666    3.485    4.933    6.448    Rosa
16.87    15.65    0.8648    6.139    3.463    3.696    5.967    Rosa
19.31    16.59    0.8815    6.341    3.81    3.477    6.238    Rosa
18.98    16.57    0.8687    6.449    3.552    2.144    6.453    Rosa
18.17    16.26    0.8637    6.271    3.512    2.853    6.273    Rosa
18.72    16.34    0.881    6.219    3.684    2.188    6.097    Rosa
16.41    15.25    0.8866    5.718    3.525    4.217    5.618    Rosa
17.99    15.86    0.8992    5.89    3.694    2.068    5.837    Rosa
19.46    16.5    0.8985    6.113    3.892    4.308    6.009    Rosa
19.18    16.63    0.8717    6.369    3.681    3.357    6.229    Rosa
18.95    16.42    0.8829    6.248    3.755    3.368    6.148    Rosa
18.83    16.29    0.8917    6.037    3.786    2.553    5.879    Rosa
18.85    16.17    0.9056    6.152    3.806    2.843    6.2    Rosa
17.63    15.86    0.88    6.033    3.573    3.747    5.929    Rosa
19.94    16.92    0.8752    6.675    3.763    3.252    6.55    Rosa
18.55    16.22    0.8865    6.153    3.674    1.738    5.894    Rosa
18.45    16.12    0.8921    6.107    3.769    2.235    5.794    Rosa
19.38    16.72    0.8716    6.303    3.791    3.678    5.965    Rosa
19.13    16.31    0.9035    6.183    3.902    2.109    5.924    Rosa
19.14    16.61    0.8722    6.259    3.737    6.682    6.053    Rosa
20.97    17.25    0.8859    6.563    3.991    4.677    6.316    Rosa
19.06    16.45    0.8854    6.416    3.719    2.248    6.163    Rosa
18.96    16.2    0.9077    6.051    3.897    4.334    5.75    Rosa
19.15    16.45    0.889    6.245    3.815    3.084    6.185    Rosa
18.89    16.23    0.9008    6.227    3.769    3.639    5.966    Rosa
20.03    16.9    0.8811    6.493    3.857    3.063    6.32    Rosa
20.24    16.91    0.8897    6.315    3.962    5.901    6.188    Rosa
18.14    16.12    0.8772    6.059    3.563    3.619    6.011    Rosa
16.17    15.38    0.8588    5.762    3.387    4.286    5.703    Rosa
18.43    15.97    0.9077    5.98    3.771    2.984    5.905    Rosa
15.99    14.89    0.9064    5.363    3.582    3.336    5.144    Rosa
18.75    16.18    0.8999    6.111    3.869    4.188    5.992    Rosa
18.65    16.41    0.8698    6.285    3.594    4.391    6.102    Rosa
17.98    15.85    0.8993    5.979    3.687    2.257    5.919    Rosa
20.16    17.03    0.8735    6.513    3.773    1.91    6.185    Rosa
17.55    15.66    0.8991    5.791    3.69    5.366    5.661    Rosa
18.3    15.89    0.9108    5.979    3.755    2.837    5.962    Rosa
18.94    16.32    0.8942    6.144    3.825    2.908    5.949    Rosa
15.38    14.9    0.8706    5.884    3.268    4.462    5.795    Rosa
16.16    15.33    0.8644    5.845    3.395    4.266    5.795    Rosa
15.56    14.89    0.8823    5.776    3.408    4.972    5.847    Rosa
15.38    14.66    0.899    5.477    3.465    3.6    5.439    Rosa
17.36    15.76    0.8785    6.145    3.574    3.526    5.971    Rosa
15.57    15.15    0.8527    5.92    3.231    2.64    5.879    Rosa
15.6    15.11    0.858    5.832    3.286    2.725    5.752    Rosa
16.23    15.18    0.885    5.872    3.472    3.769    5.922    Rosa
13.07    13.92    0.848    5.472    2.994    5.304    5.395    Canadian
13.32    13.94    0.8613    5.541    3.073    7.035    5.44    Canadian
13.34    13.95    0.862    5.389    3.074    5.995    5.307    Canadian
12.22    13.32    0.8652    5.224    2.967    5.469    5.221    Canadian
11.82    13.4    0.8274    5.314    2.777    4.471    5.178    Canadian
11.21    13.13    0.8167    5.279    2.687    6.169    5.275    Canadian
11.43    13.13    0.8335    5.176    2.719    2.221    5.132    Canadian
12.49    13.46    0.8658    5.267    2.967    4.421    5.002    Canadian
12.7    13.71    0.8491    5.386    2.911    3.26    5.316    Canadian
10.79    12.93    0.8107    5.317    2.648    5.462    5.194    Canadian
11.83    13.23    0.8496    5.263    2.84    5.195    5.307    Canadian
12.01    13.52    0.8249    5.405    2.776    6.992    5.27    Canadian
12.26    13.6    0.8333    5.408    2.833    4.756    5.36    Canadian
11.18    13.04    0.8266    5.22    2.693    3.332    5.001    Canadian
11.36    13.05    0.8382    5.175    2.755    4.048    5.263    Canadian
11.19    13.05    0.8253    5.25    2.675    5.813    5.219    Canadian
11.34    12.87    0.8596    5.053    2.849    3.347    5.003    Canadian
12.13    13.73    0.8081    5.394    2.745    4.825    5.22    Canadian
11.75    13.52    0.8082    5.444    2.678    4.378    5.31    Canadian
11.49    13.22    0.8263    5.304    2.695    5.388    5.31    Canadian
12.54    13.67    0.8425    5.451    2.879    3.082    5.491    Canadian
12.02    13.33    0.8503    5.35    2.81    4.271    5.308    Canadian
12.05    13.41    0.8416    5.267    2.847    4.988    5.046    Canadian
12.55    13.57    0.8558    5.333    2.968    4.419    5.176    Canadian
11.14    12.79    0.8558    5.011    2.794    6.388    5.049    Canadian
12.1    13.15    0.8793    5.105    2.941    2.201    5.056    Canadian
12.44    13.59    0.8462    5.319    2.897    4.924    5.27    Canadian
12.15    13.45    0.8443    5.417    2.837    3.638    5.338    Canadian
11.35    13.12    0.8291    5.176    2.668    4.337    5.132    Canadian
11.24    13.0    0.8359    5.09    2.715    3.521    5.088    Canadian
11.02    13.0    0.8189    5.325    2.701    6.735    5.163    Canadian
11.55    13.1    0.8455    5.167    2.845    6.715    4.956    Canadian
11.27    12.97    0.8419    5.088    2.763    4.309    5.0    Canadian
11.4    13.08    0.8375    5.136    2.763    5.588    5.089    Canadian
10.83    12.96    0.8099    5.278    2.641    5.182    5.185    Canadian
10.8    12.57    0.859    4.981    2.821    4.773    5.063    Canadian
11.26    13.01    0.8355    5.186    2.71    5.335    5.092    Canadian
10.74    12.73    0.8329    5.145    2.642    4.702    4.963    Canadian
11.48    13.05    0.8473    5.18    2.758    5.876    5.002    Canadian
12.21    13.47    0.8453    5.357    2.893    1.661    5.178    Canadian
11.41    12.95    0.856    5.09    2.775    4.957    4.825    Canadian
12.46    13.41    0.8706    5.236    3.017    4.987    5.147    Canadian
12.19    13.36    0.8579    5.24    2.909    4.857    5.158    Canadian
11.65    13.07    0.8575    5.108    2.85    5.209    5.135    Canadian
12.89    13.77    0.8541    5.495    3.026    6.185    5.316    Canadian
11.56    13.31    0.8198    5.363    2.683    4.062    5.182    Canadian
11.81    13.45    0.8198    5.413    2.716    4.898    5.352    Canadian
10.91    12.8    0.8372    5.088    2.675    4.179    4.956    Canadian
11.23    12.82    0.8594    5.089    2.821    7.524    4.957    Canadian
10.59    12.41    0.8648    4.899    2.787    4.975    4.794    Canadian
10.93    12.8    0.839    5.046    2.717    5.398    5.045    Canadian
11.27    12.86    0.8563    5.091    2.804    3.985    5.001    Canadian
11.87    13.02    0.8795    5.132    2.953    3.597    5.132    Canadian
10.82    12.83    0.8256    5.18    2.63    4.853    5.089    Canadian
12.11    13.27    0.8639    5.236    2.975    4.132    5.012    Canadian
12.8    13.47    0.886    5.16    3.126    4.873    4.914    Canadian
12.79    13.53    0.8786    5.224    3.054    5.483    4.958    Canadian
13.37    13.78    0.8849    5.32    3.128    4.67    5.091    Canadian
12.62    13.67    0.8481    5.41    2.911    3.306    5.231    Canadian
12.76    13.38    0.8964    5.073    3.155    2.828    4.83    Canadian
12.38    13.44    0.8609    5.219    2.989    5.472    5.045    Canadian
12.67    13.32    0.8977    4.984    3.135    2.3    4.745    Canadian
11.18    12.72    0.868    5.009    2.81    4.051    4.828    Canadian
12.7    13.41    0.8874    5.183    3.091    8.456    5.0    Canadian
12.37    13.47    0.8567    5.204    2.96    3.919    5.001    Canadian
12.19    13.2    0.8783    5.137    2.981    3.631    4.87    Canadian
11.23    12.88    0.8511    5.14    2.795    4.325    5.003    Canadian
13.2    13.66    0.8883    5.236    3.232    8.315    5.056    Canadian
11.84    13.21    0.8521    5.175    2.836    3.598    5.044    Canadian
12.3    13.34    0.8684    5.243    2.974    5.637    5.063    Canadian

第一步:加载数据

load.py

import numpy as np

def load_dataset(dataset_name):
    data = []
    label = []
    with open(‘{0}.tsv‘.format(dataset_name),‘r‘) as f:
        lines = f.readlines()
        for line in lines:
            linedata = line.strip().split(‘\t‘)
            data.append([float(da) for da in linedata[:-1]])
            label.append(linedata[-1])
        data = np.array(data)
        label = np.array(label)
    return data,label

第二步:设计分类模型

阈值分类模型是在所有的训练数据中找最佳的阈值,这个阈值使得训练集的预测效果最好。

threshold.py

#coding:utf-8
import numpy as np

def learn_model(features,labels):
    best_acc = -1.0
    thresh = features.copy()
    for fi in range(features.shape[1]): # 逐列
        thresh = features[:,fi].copy()
        thresh.sort()
        for t in thresh: # 列中每一个元素
            pred = (features[:,fi]>t)
            acc = (pred == labels).mean()
            if acc > best_acc:
                best_acc = acc
                best_fi = fi
                best_t = t
    print ‘model->best_fi,t,acc:‘,best_fi,best_t,best_acc
    return best_t,best_fi

def apply_model(features,model):
    t,fi = model
    return features[:,fi] > t    

def accurcy(features,labels,model):
    predictions = apply_model(features,model)
    return (predictions == labels).mean() #prediction == labels 同为真或同为假
    

第三步:测试模型的预测准确性

在这里采用十折交叉验证,即把样本数据分成10份,每次取其中一份作为测试数据,其余9份作为训练数据。这种方法的优点是充分利用了数据样本资源,缺点是计算量大。

seeds_threshold.py

#coding:utf-8
from load import load_dataset
import numpy as np
from threshold import learn_model,accurcy,apply_model

features,labels = load_dataset(‘seeds‘)
labels = (labels ==‘Canadian‘) #相等就为 True 不相等就为 False
sumacc = 0.0
for flod in xrange(10):
    print ‘第 ‘,flod+1,‘ 次交叉验证‘
    training = np.ones(len(features),bool)
    training[flod::10] = False
    testing = ~training
    model = learn_model(features[training],labels[training])
    acc = accurcy(features[testing],labels[testing],model)
    print ‘测试集预测准确率{0:.1%}‘.format(acc)
    sumacc += acc
sumacc /= 10
print ‘平均测试集预测准确率{0:.1%}‘.format(sumacc)

运行 seeds_threshold.py

这样下来一个简单的阈值分类模型就建好了。

第五次交叉验证的准确率都是 81% 分类的阈值分别是第 fi=5 列,t = 4.308.我们就可以用这个阈值预测给定种子是否是 Canadian.

现在我们在已有的基础上把三种 seed 的分类阈值都求出来:

seeds.py

#coding:utf-8
from load import load_dataset
import numpy as np
from threshold import learn_model,accurcy,apply_model
features,rawlabels = load_dataset(‘seeds‘)
labelset  = set(rawlabels)
print labelset
#labels = (labels ==‘Canadian‘) #相等就为 True 不相等就为 False
for label in labelset:
    print label
    labels = rawlabels.copy()
    labels = (labels == label)
    sumacc = 0.0
    bestacc = 0.0
    for flod in xrange(10):
        print ‘第 ‘,flod+1,‘ 次交叉验证‘
        training = np.ones(len(features),bool)
        training[flod::10] = False
        testing = ~training
        model = learn_model(features[training],labels[training])
        acc = accurcy(features[testing],labels[testing],model)
        print ‘测试集预测准确率{0:.1%}‘.format(acc)
        if acc > bestacc:
            bestacc = acc
            bestmodel = model
        sumacc += acc
    sumacc /= 10
    print ‘平均测试集预测准确率{0:.1%}‘.format(sumacc)
    print ‘最佳模型:‘,model    

分别求得各个类别的分类阈值。

根据阈值可以画出分类树。

用data表示一个待分类数据 data 有 7个元素,分别表示 7 个不同的特征。

分类树:

时间: 2024-10-22 02:16:25

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