6个指标采用熵值法进行权重分析sql实例
时间: 2024-02-23 15:58:10 浏览: 28
假设有一个包含6个指标的数据表,其中各指标的得分分别为score1,score2,score3,score4,score5和score6,可以使用如下SQL语句进行熵值法进行权重分析:
```
SELECT
score1,
score2,
score3,
score4,
score5,
score6,
(score1*w1+score2*w2+score3*w3+score4*w4+score5*w5+score6*w6) AS total_score
FROM
(SELECT
score1,
score2,
score3,
score4,
score5,
score6,
(score1/(SELECT SUM(score1) FROM table_name))*LOG(score1/(SELECT SUM(score1) FROM table_name)) AS w1,
(score2/(SELECT SUM(score2) FROM table_name))*LOG(score2/(SELECT SUM(score2) FROM table_name)) AS w2,
(score3/(SELECT SUM(score3) FROM table_name))*LOG(score3/(SELECT SUM(score3) FROM table_name)) AS w3,
(score4/(SELECT SUM(score4) FROM table_name))*LOG(score4/(SELECT SUM(score4) FROM table_name)) AS w4,
(score5/(SELECT SUM(score5) FROM table_name))*LOG(score5/(SELECT SUM(score5) FROM table_name)) AS w5,
(score6/(SELECT SUM(score6) FROM table_name))*LOG(score6/(SELECT SUM(score6) FROM table_name)) AS w6
FROM
table_name
) AS w_scores;
```
在上述SQL语句中,先通过子查询将各指标的得分进行权重计算,然后计算各指标的加权得分,最后得到总分。其中,权重的计算采用熵值法,具体权重计算公式为:
$w_i=\frac{s_i*ln(s_i)}{\sum_{i=1}^ns_i*ln(s_i)}$
其中,$s_i$表示第i个指标得分的归一化值,$w_i$表示第i个指标的权重。在上述SQL语句中,权重的计算部分和加权得分部分被整合到了一起,因此可以一次性得到各指标的加权得分和总分。