计算外部指标 rand_index = rand_score(iris_target, clusters) fmi = fowlkes_mallows_score(iris_target, clusters),其中iris_target是什么意思
时间: 2024-04-05 16:33:56 浏览: 65
iris_target指的是鸢尾花数据集中每个样本所属的真实类别标签,是一个一维的数组或列表。rand_index和fmi是聚类算法的外部评价指标,用于评估聚类结果与真实类别标签的匹配程度。其中,rand_score计算的是聚类结果与真实类别标签的一致性,取值在0到1之间,越接近1表示聚类结果越好;fowlkes_mallows_score计算的是聚类结果中同一类别内的样本相似度和不同类别之间的样本差异度,取值在0到1之间,越接近1表示聚类结果越好。
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import numpy as np import pandas as pd from sklearn.decomposition import PCA import matplotlib.pyplot as plt # 加载数据集 iris = pd.read_csv('iris_pca.csv') X = iris.iloc[:, :-1] y = iris.iloc[:, -1] # PCA降维 pca = PCA(n_components=2) X_pca = pca.fit_transform(X) # DBSCAN聚类 def dbscan(X, eps=0.5, min_samples=5): m, n = X.shape visited = np.zeros(m, dtype=bool) labels = np.zeros(m, dtype=int) cluster_id = 1 for i in range(m): if not visited[i]: visited[i] = True neighbors = get_neighbors(X, i, eps) if len(neighbors) < min_samples: labels[i] = -1 else: expand_cluster(X, i, neighbors, visited, labels, cluster_id, eps, min_samples) cluster_id += 1 return labels def get_neighbors(X, i, eps): dists = np.sum((X - X[i]) ** 2, axis=1) neighbors = np.where(dists < eps ** 2)[0] return neighbors def expand_cluster(X, i, neighbors, visited, labels, cluster_id, eps, min_samples): labels[i] = cluster_id for j in neighbors: if not visited[j]: visited[j] = True new_neighbors = get_neighbors(X, j, eps) if len(new_neighbors) >= min_samples: neighbors = np.union1d(neighbors, new_neighbors) if labels[j] == 0: labels[j] = cluster_id labels = dbscan(X_pca, eps=0.5, min_samples=5) # 簇的总数 n_clusters = len(set(labels)) - (1 if -1 in labels else 0) print("簇的总数:", n_clusters) # 各样本所归属簇的编号 print("各样本所归属簇的编号:", labels) # 外部指标 from sklearn.metrics import adjusted_rand_score, fowlkes_mallows_score ri = adjusted_rand_score(y, labels) fmi = fowlkes_mallows_score(y, labels) print("RI:", ri) print("FMI:", fmi) # 内部指标 from sklearn.metrics import davies_bouldin_score dbi = davies_bouldin_score(X_pca, labels) print("DBI:", dbi) # 可视化输出 plt.scatter(X_pca[:, 0], X_pca[:, 1], c=labels) plt.show(),请为我分析这段代码的运行结果
这段代码首先使用PCA对iris数据集进行降维,将数据降到了2维。然后使用自己实现的DBSCAN聚类算法对降维后的数据进行聚类,其中eps和min_samples是DBSCAN算法的超参数。聚类完成后,输出簇的总数和各样本所归属簇的编号。接着计算聚类结果的外部指标RI和FMI,以及内部指标DBI,并将聚类结果可视化。
RI和FMI都是用来评估聚类结果和真实标签之间的相似度的指标,RI的取值范围为[-1, 1],取值越接近1说明聚类结果越好;FMI的取值范围也为[0, 1],取值越接近1说明聚类结果越好。DBI是一种内部评价指标,用于评估聚类结果的紧密度和分离度,取值越小说明聚类结果越好。
最后的可视化结果将聚类结果以不同颜色的散点图展示出来,便于直观观察聚类效果。
修改代码from pandas import user=read_csv(APP】 cSV encoding='gbk') userL =user 概率].fi11na(0.0) user Fuser fi11na(0.0) user 愿分 享概 user <0]=0 user 享概率 user 1 user 愿喜久 率 user 0」 user 唇分享 率 user 享概率 >1 =1 user user 克击 =’T]=1 user[是否点击分享 LuserL 是古点击分享 ’F1=0 user.to_csv(user_clean.csv index=False) user_clean=read_csv(user_clean.csv' coding a:0,b:1,'c:2, d:3, e:4, r12 5 k:10,1:11, D6E8了8 2t:19,'u:20,'v:21, x:23, :24, 三是5,王三工·三工 def tocode(s): code =0 ss.lower()[o] if s in coding.keys(): code coding[s] return code user_clean['用户编码']=user_clean["用户名"门N apply(lambda x:tocode (x)) user_clean["分组后在线时长=qcut(user-cleanl在线时长"],\ 4,1abe1s=[4,3,2,1]) user_clean.to_csv('user_feature.csv',index=False) from numpy import from sklearn.cluster import KMeans from sklearn.metrics import fowlkes_mallows_score user_feature read_csv(user_feature.csv X=user_feature[不愿分享概率,'愿意分享概率',在线时长',\ 分后在线时长方 在线时长卢, y=user_feature['是香点击分享 y=list(y) model KMeans(n_clusters=2).fit(X) model.labels_=list (model.labels_) score=fowlkes_mallows_score(y,model.labels_) print('FMI评价分值为:%f%score).
抱歉,这段代码有很多错误,需要进行修改。以下是修改后的代码:
```
import pandas as pd
import numpy as np
from sklearn.cluster import KMeans
from sklearn.metrics import fowlkes_mallows_score
# 读取原始数据
user = pd.read_csv("APP.csv", encoding='gbk')
# 处理缺失值
user.fillna(0.0, inplace=True)
# 处理用户分享概率小于0的情况
user.loc[user["不愿分享概率"] < 0, "不愿分享概率"] = 0
# 处理用户分享概率大于1的情况
user.loc[user["不愿分享概率"] > 1, "不愿分享概率"] = 1
# 处理用户是否点击分享
user["是否点击分享"] = user["是香点击分享"].apply(lambda x: 1 if x == 'T' else 0)
# 用户编码
coding = {'a': 0, 'b': 1, 'c': 2, 'd': 3, 'e': 4, 'r': 12, 'k': 10, 'l': 11, 't': 19, 'u': 20, 'v': 21, 'x': 23, 'y': 24}
def tocode(s):
code = 0
for c in s.lower():
if c in coding.keys():
code = code * 26 + coding[c]
return code
user["用户编码"] = user["用户名"].apply(lambda x: tocode(x))
# 分组后在线时长
user["分组后在线时长"] = pd.qcut(user["在线时长"], 4, labels=[4, 3, 2, 1])
# 保存处理后的数据
user_clean = user[["用户编码", "不愿分享概率", "愿意分享概率", "在线时长", "分组后在线时长", "是否点击分享"]]
user_clean.to_csv("user_clean.csv", index=False)
# 特征工程
user_feature = pd.read_csv("user_clean.csv")
# K-Means聚类
X = user_feature[["不愿分享概率", "愿意分享概率", "在线时长", "分组后在线时长"]]
y = user_feature["是否点击分享"]
model = KMeans(n_clusters=2).fit(X)
model.labels_ = list(model.labels_)
score = fowlkes_mallows_score(y, model.labels_)
print('FMI评价分值为:%f' % score)
```
这段代码的功能是对用户数据进行一系列处理和特征工程,最后使用KMeans算法进行聚类并输出FMI评价分值。
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