信号检测准确性的ROC曲线分析

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资源摘要信息: "ROC曲线.zip" 文件包含了用于信号检测的ROC曲线计算的相关MATLAB脚本文件。文件中的"roc_estimated.m"和"ROC_energy.m"脚本文件涉及接收者操作特征(Receiver Operating Characteristic,简称ROC)曲线的估计与分析。ROC曲线是一种图形化的工具,广泛用于评估和比较分类模型在不同阈值设置下的性能。在信号检测领域,ROC曲线尤其重要,因为它能够展示检测系统的真正类率(True Positive Rate,简称TPR)与假正类率(False Positive Rate,简称FPR)之间的权衡关系。通过ROC曲线,可以直观地理解模型在各种决策条件下的表现,比如在提高检出率的同时是否会导致更高的误报率。 ROC曲线的核心概念包括真正类率(TPR)和假正类率(FPR)。TPR是指正确识别为正例的数量占实际正例总数的比例,FPR则是指错误地识别为正例的数量占实际负例总数的比例。ROC曲线下面积(Area Under Curve,简称AUC)是一个衡量分类器好坏的指标,AUC值越高,说明分类器在判断正负类别时越准确。 "roc_estimated.m"文件很可能包含了估计ROC曲线的算法,以及如何根据不同的阈值计算TPR和FPR。这个文件可能会包含绘制ROC曲线的代码,并计算AUC值,用以评估检测算法的性能。 "ROC_energy.m"文件可能涉及到信号的处理与特征提取,因为信号能量是信号检测中的一个重要特征。该文件可能会计算信号的能量,作为分类器的一个输入特征,进一步用于生成ROC曲线。通过分析信号能量,可以对信号的强度有一个量化的认识,并用这一信息来优化信号检测算法。 在进行信号检测时,ROC曲线是一个非常有用的工具,因为它能够帮助研究者和工程师在不同的检测阈值之间找到最佳的平衡点。通过比较不同检测算法或配置下的ROC曲线,可以直观地看出哪种方法在保持高检出率的同时能够最小化误报率。此外,如果一个检测系统在各种不同的应用中都能展现出较高的AUC值,那么我们可以认为这个系统在信号检测方面具有较好的泛化能力。 总之,"ROC曲线.zip"文件的分析与应用要求研究者具备良好的信号处理知识,以及对ROC曲线和AUC值的理解。通过这些脚本文件,用户可以对信号检测系统进行深入的性能评估,并为实际应用中优化检测策略提供理论依据和技术支持。

import seaborn as sns corrmat = df.corr() top_corr_features = corrmat.index plt.figure(figsize=(16,16)) #plot heat map g=sns.heatmap(df[top_corr_features].corr(),annot=True,cmap="RdYlGn") plt.show() sns.set_style('whitegrid') sns.countplot(x='target',data=df,palette='RdBu_r') plt.show() dataset = pd.get_dummies(df, columns = ['sex', 'cp', 'fbs','restecg', 'exang', 'slope', 'ca', 'thal']) from sklearn.model_selection import train_test_split from sklearn.preprocessing import StandardScaler standardScaler = StandardScaler() columns_to_scale = ['age', 'trestbps', 'chol', 'thalach', 'oldpeak'] dataset[columns_to_scale] = standardScaler.fit_transform(dataset[columns_to_scale]) dataset.head() y = dataset['target'] X = dataset.drop(['target'], axis=1) from sklearn.model_selection import cross_val_score knn_scores = [] for k in range(1, 21): knn_classifier = KNeighborsClassifier(n_neighbors=k) score = cross_val_score(knn_classifier, X, y, cv=10) knn_scores.append(score.mean()) plt.plot([k for k in range(1, 21)], knn_scores, color='red') for i in range(1, 21): plt.text(i, knn_scores[i - 1], (i, knn_scores[i - 1])) plt.xticks([i for i in range(1, 21)]) plt.xlabel('Number of Neighbors (K)') plt.ylabel('Scores') plt.title('K Neighbors Classifier scores for different K values') plt.show() knn_classifier = KNeighborsClassifier(n_neighbors = 12) score=cross_val_score(knn_classifier,X,y,cv=10) score.mean() from sklearn.ensemble import RandomForestClassifier randomforest_classifier= RandomForestClassifier(n_estimators=10) score=cross_val_score(randomforest_classifier,X,y,cv=10) score.mean()的roc曲线的代码

2023-05-09 上传

修正下列代码y_test=np.array(y_test) y_score=np.array(y_score) fpr = dict() tpr = dict() roc_auc = dict() for i in range(n_classes): # 遍历三个类别 fpr[i], tpr[i], _ = roc_curve(y_test[:, i], y_score[:, i]) roc_auc[i] = auc(fpr[i], tpr[i]) # Compute micro-average ROC curve and ROC area(方法二) fpr["micro"], tpr["micro"], _ = roc_curve(y_test.ravel(), y_score.ravel()) roc_auc["micro"] = auc(fpr["micro"], tpr["micro"]) # Compute macro-average ROC curve and ROC area(方法一) # First aggregate all false positive rates all_fpr = np.unique(np.concatenate([fpr[i] for i in range(n_classes)])) # Then interpolate all ROC curves at this points mean_tpr = np.zeros_like(all_fpr) for i in range(n_classes): mean_tpr += interp(all_fpr, fpr[i], tpr[i]) # Finally average it and compute AUC mean_tpr /= n_classes fpr["macro"] = all_fpr tpr["macro"] = mean_tpr roc_auc["macro"] = auc(fpr["macro"], tpr["macro"]) # Plot all ROC curves lw=2 plt.figure() plt.plot(fpr["micro"], tpr["micro"], label='micro-average ROC curve (area = {0:0.2f})' ''.format(roc_auc["micro"]), color='deeppink', linestyle=':', linewidth=4) plt.plot(fpr["macro"], tpr["macro"], label='macro-average ROC curve (area = {0:0.2f})' ''.format(roc_auc["macro"]), color='navy', linestyle=':', linewidth=4) colors = cycle(['aqua', 'darkorange', 'cornflowerblue']) for i, color in zip(range(n_classes), colors): plt.plot(fpr[i], tpr[i], color=color, lw=lw, label='ROC curve of class {0} (area = {1:0.2f})' ''.format(i, roc_auc[i])) plt.plot([0, 1], [0, 1], 'k--', lw=lw) plt.xlim([0.0, 1.0]) plt.ylim([0.0, 1.05]) plt.xlabel('False Positive Rate') plt.ylabel('True Positive Rate') plt.title('Some extension of Receiver operating characteristic to multi-class') plt.legend(loc="lower right") plt.show()

2023-05-25 上传

for each class class_names = np.unique(y_train) y_scores = tree.predict_proba(X_test) y_pred = tree.predict(X_test) macro_auc = roc_auc_score(y_test, y_scores, multi_class='ovo', average='macro') y_test = label_binarize(y_test, classes=range(3)) y_pred = label_binarize(y_pred, classes=range(3)) micro_auc = roc_auc_score(y_test, y_scores, average='micro') #micro_auc = roc_auc_score(y_test, y_scores, multi_class='ovr', average='micro') # calculate ROC curve fpr = dict() tpr = dict() roc_auc = dict() for i in range(3): # 遍历三个类别 fpr[i], tpr[i], _ = roc_curve(y_test[:, i], y_pred[:, i]) roc_auc[i] = auc(fpr[i], tpr[i]) return reports, matrices, micro_auc, macro_auc, fpr, tpr, roc_auc根据上述代码怎么调整下列代码fpr["micro"], tpr["micro"], _ = roc_curve(y_test.ravel(), y_pred.ravel()) roc_auc["micro"] = auc(fpr["micro"], tpr["micro"]) # Compute macro-average ROC curve and ROC area(方法一) # First aggregate all false positive rates all_fpr = np.unique(np.concatenate([fpr_avg[i] for i in range(3)])) # Then interpolate all ROC curves at this points mean_tpr = np.zeros_like(all_fpr) for i in range(3): mean_tpr += interp(all_fpr, fpr_avg[i], tpr_avg[i]) # Finally average it and compute AUC mean_tpr /= 3 fpr_avg["macro"] = all_fpr tpr_avg["macro"] = mean_tpr macro_auc_avg["macro"] = macro_auc_avg # Plot all ROC curves lw = 2 plt.figure() plt.plot(fpr_avg["micro"], tpr_avg["micro"], label='micro-average ROC curve (area = {0:0.2f})' ''.format(micro_auc_avg["micro"]), color='deeppink', linestyle=':', linewidth=4) plt.plot(fpr_avg["macro"], tpr_avg["macro"], label='macro-average ROC curve (area = {0:0.2f})' ''.format(macro_auc_avg["macro"]), color='navy', linestyle=':', linewidth=4) colors = cycle(['aqua', 'darkorange', 'cornflowerblue']) for i, color in zip(range(3), colors): plt.plot(fpr_avg[i], tpr_avg[i], color=color, lw=lw, label='ROC curve of class {0} (area = {1:0.2f})' ''.format(i, roc_auc_avg[i])) plt.plot([0, 1], [0, 1], 'k--', lw=lw) plt.xlim([0.0, 1.0]) plt.ylim([0.0, 1.05]) plt.xlabel('False Positive Rate') plt.ylabel('True Positive Rate') plt.title('DF') plt.legend(loc="lower right") plt.show()

2023-06-02 上传

随机森林导入数据用kfold分层抽样后用下列画roc_curve曲线三分类python代码mse = mean_squared_error(y_test, y_pred1) rmse = math.sqrt(mse) print('FNN深度森林RMSE:', rmse) print('FNN深度森林Accuracy:', accuracy_score(y_test, y_pred1)) mse = mean_squared_error(y_test_fuzzy, y_pred) rmse = math.sqrt(mse) print('深度森林RMSE:', rmse) print('深度森林Accuracy:', accuracy_score(y_test_fuzzy, y_pred)) fpr = dict() tpr = dict() roc_auc = dict() for i in range(3): # 遍历三个类别 fpr[i], tpr[i], _ = roc_curve(y_test[:, i], y_pred1[:, i]) roc_auc[i] = auc(fpr[i], tpr[i]) # Compute micro-average ROC curve and ROC area(方法二) fpr["micro"], tpr["micro"], _ = roc_curve(y_test.ravel(), y_pred1.ravel()) roc_auc["micro"] = auc(fpr["micro"], tpr["micro"]) # Compute macro-average ROC curve and ROC area(方法一) # First aggregate all false positive rates all_fpr = np.unique(np.concatenate([fpr[i] for i in range(3)])) # Then interpolate all ROC curves at this points mean_tpr = np.zeros_like(all_fpr) for i in range(3): mean_tpr += interp(all_fpr, fpr[i], tpr[i]) # Finally average it and compute AUC mean_tpr /= 3 fpr["macro"] = all_fpr tpr["macro"] = mean_tpr roc_auc["macro"] = auc(fpr["macro"], tpr["macro"]) # Plot all ROC curves lw = 2 plt.figure() plt.plot(fpr["micro"], tpr["micro"], label='micro-average ROC curve (area = {0:0.2f})' ''.format(roc_auc["micro"]), color='deeppink', linestyle=':', linewidth=4) plt.plot(fpr["macro"], tpr["macro"], label='macro-average ROC curve (area = {0:0.2f})' ''.format(roc_auc["macro"]), color='navy', linestyle=':', linewidth=4) colors = cycle(['aqua', 'darkorange', 'cornflowerblue']) for i, color in zip(range(3), colors): plt.plot(fpr[i], tpr[i], color=color, lw=lw, label='ROC curve of class {0} (area = {1:0.2f})' ''.format(i, roc_auc[i])) plt.plot([0, 1], [0, 1], 'k--', lw=lw) plt.xlim([0.0, 1.0]) plt.ylim([0.0, 1.05]) plt.xlabel('False Positive Rate') plt.ylabel('True Positive Rate') plt.title('DF-F') plt.legend(loc="lower right")

2023-06-01 上传