矩偏度系数
在统计学中,定义非组变量和组变量的 k 阶样本中心矩分别为
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---
Reason: Response code 404 (Not Found)
---
Fetch details:
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"date": "Tue, 17 Sep 2024 08:27:36 GMT",
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"connection": "close"
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--- 和 Error creating node with https://www.google.com/chart?cht=tx&chf=bg,s,FFFFFF00&chco=000000&chl=V_%7Bk%7D%20%3D%20%5Cfrac%7B%5Csum_%7Bi%3D1%7D%5E%7Bn%7Df_%7Bi%7D(x_%7Bi%7D-%5Cbar%7Bx%7D)%5E%7Bk%7D%7D%7B%5Csum_%7Bi%3D1%7D%5E%7Bn%7Df_%7Bi%7D-1%7D. Unable to fetch:
https://www.google.com/chart?cht=tx&chf=bg,s,FFFFFF00&chco=000000&chl=V_%7Bk%7D%20%3D%20%5Cfrac%7B%5Csum_%7Bi%3D1%7D%5E%7Bn%7Df_%7Bi%7D(x_%7Bi%7D-%5Cbar%7Bx%7D)%5E%7Bk%7D%7D%7B%5Csum_%7Bi%3D1%7D%5E%7Bn%7Df_%7Bi%7D-1%7D
---
Reason: Response code 404 (Not Found)
---
Fetch details:
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"method": "GET",
"errorCode": "ERR_NON_2XX_3XX_RESPONSE",
"responseStatusCode": 404,
"responseStatusMessage": "Not Found",
"requestHeaders": {
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"accept-encoding": "gzip, deflate, br"
},
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"date": "Tue, 17 Sep 2024 08:27:58 GMT",
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"connection": "close"
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---
当分布对称时,奇数阶中心矩应为零,而一阶矩恒为零,因此可以用消除量纲的三阶矩来度量偏度,对应组数据和非组数据的矩偏度系数为
矩偏度系数 = Error creating node with https://www.google.com/chart?cht=tx&chf=bg,s,FFFFFF00&chco=000000&chl=%5Cfrac%7B%5Cfrac%7B%5Csum_%7Bi%3D1%7D%5E%7Bn%7D(x_%7Bi%7D%20-%20%5Cbar%20%7Bx%7D)%5E3%7D%7Bn-1%7D%7D%7B%5Cleft(%5Cfrac%7B%5Csum_%7Bi%3D1%7D%5E%7Bn%7D(x_i%20-%20%5Cbar%7Bx%7D)%5E2%7D%7Bn-1%7D%5Cright)%5E3%7D. Unable to fetch:
https://www.google.com/chart?cht=tx&chf=bg,s,FFFFFF00&chco=000000&chl=%5Cfrac%7B%5Cfrac%7B%5Csum_%7Bi%3D1%7D%5E%7Bn%7D(x_%7Bi%7D%20-%20%5Cbar%20%7Bx%7D)%5E3%7D%7Bn-1%7D%7D%7B%5Cleft(%5Cfrac%7B%5Csum_%7Bi%3D1%7D%5E%7Bn%7D(x_i%20-%20%5Cbar%7Bx%7D)%5E2%7D%7Bn-1%7D%5Cright)%5E3%7D
---
Reason: Response code 404 (Not Found)
---
Fetch details:
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"method": "GET",
"errorCode": "ERR_NON_2XX_3XX_RESPONSE",
"responseStatusCode": 404,
"responseStatusMessage": "Not Found",
"requestHeaders": {
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"accept-encoding": "gzip, deflate, br"
},
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"date": "Tue, 17 Sep 2024 08:28:05 GMT",
"alt-svc": "h3=\":443\"; ma=2592000,h3-29=\":443\"; ma=2592000",
"connection": "close"
}
}
--- 和 Error creating node with https://www.google.com/chart?cht=tx&chf=bg,s,FFFFFF00&chco=000000&chl=%5Cfrac%7B%5Cfrac%7B%5Csum_%7Bi%3D1%7D%5E%7Bn%7Df_i(x_i-%5Cbar%7Bx%7D)%5E3%7D%7B%5Csum_%7Bi%3D1%7D%5E%7Bn%7Df_i-1%7D%7D%7B%5Cleft%5B%20%5Cfrac%7B%5Csum_%7Bi%3D1%7D%5E%7Bn%7Df_i(x_i-%5Cbar%7Bx%7D)%5E2%7D%7B%5Csum_%7Bx%3D1%7D%5E%7Bn%7Df_i-1%7D%20%5Cright%5D%5E3%20%7D. Unable to fetch:
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---
Reason: Response code 404 (Not Found)
---
Fetch details:
{
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"method": "GET",
"errorCode": "ERR_NON_2XX_3XX_RESPONSE",
"responseStatusCode": 404,
"responseStatusMessage": "Not Found",
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"user-agent": "got (https://github.com/sindresorhus/got)",
"accept-encoding": "gzip, deflate, br"
},
"responseHeaders": {
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"referrer-policy": "no-referrer",
"content-length": "1566",
"date": "Tue, 17 Sep 2024 08:28:12 GMT",
"alt-svc": "h3=\":443\"; ma=2592000,h3-29=\":443\"; ma=2592000",
"connection": "close"
}
}
---
示例:
https://spreadsheets.google.com/pub?key=tj37eDmCFY8wamRCBj9y22A&gid=2