Diferencia entre revisiones de «Coeficiente de concordancia simple»

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{| class="wikitable"
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! índice !! símbolo !! fórmula
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|-
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|  ||  ||
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|-
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| SMC (concordancia simple) || ''S'' || (''a'' + ''d'')/(''a'' + ''b'' + ''c'' + ''d'')
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|-
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| Jaccard || ''J'' || ''a''/(''a'' + ''b'' + ''c'')
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|-
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| Czekanovski || ''C'' || 2''a''/(2''a'' + ''b'' + ''c'')
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|-
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| Russell & Rao || ''R'' || ''a''/(''a'' + ''b'' + ''c'' + ''d'')
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|-
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| distancia euclidiana (disimilaridad) || ''?'' || [?(x''A''<sub>i</sub> - x''B''<sub>i</sub>)<sup>2</sup>]<sup>½</sup>
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|}
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a<sub>s</sub> =  
 
a<sub>s</sub> =  
  
a = ssp comunes
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:''a'' = ssp comunes
b = exclusivas de grupo 1
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:''b'' = exclusivas de grupo 1
c = exclusivas de grupo 2
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:''c'' = exclusivas de grupo 2
d = spp ausentes en común
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:''d'' = spp ausentes en común
  
  
 
[[Categoría:Glosario]] [[Categoría:Esbozo]]
 
[[Categoría:Glosario]] [[Categoría:Esbozo]]
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The simple matching coefficient (SMC) or Rand similarity coefficient is a statistic used for comparing the similarity and diversity of sample sets.[1]
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A
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0 1
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B 0 {\displaystyle M_{00}}M_{00} {\displaystyle M_{10}}M_{10}
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1 {\displaystyle M_{01}}M_{01} {\displaystyle M_{11}}M_{11}
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Given two objects, A and B, each with n binary attributes, SMC is defined as:
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{\displaystyle {\begin{aligned}{\text{SMC}}&={\frac {\text{number of matching attributes}}{\text{number of attributes}}}\\[8pt]&={\frac {M_{00}+M_{11}}{M_{00}+M_{01}+M_{10}+M_{11}}}\end{aligned}}}{\displaystyle {\begin{aligned}{\text{SMC}}&={\frac {\text{number of matching attributes}}{\text{number of attributes}}}\\[8pt]&={\frac {M_{00}+M_{11}}{M_{00}+M_{01}+M_{10}+M_{11}}}\end{aligned}}}
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where:
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{\displaystyle M_{11}}M_{11} is the total number of attributes where A and B both have a value of 1.
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{\displaystyle M_{01}}M_{01} is the total number of attributes where the attribute of A is 0 and the attribute of B is 1.
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{\displaystyle M_{10}}M_{10} is the total number of attributes where the attribute of A is 1 and the attribute of B is 0.
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{\displaystyle M_{00}}M_{00} is the total number of attributes where A and B both have a value of 0.
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The simple matching distance (SMD), which measures dissimilarity between sample sets, is given by {\displaystyle 1-{\text{SMC}}}{\displaystyle 1-{\text{SMC}}}.[2]
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SMC is linearly related to Hamann similarity: {\displaystyle SMC=(Hamann+1)/2}{\displaystyle SMC=(Hamann+1)/2}. Also, {\displaystyle SMC=1-D^{2}/n}{\displaystyle SMC=1-D^{2}/n}, where {\displaystyle D^{2}}D^{2} is the squared Euclidean distance between the two objects (binary vectors) and n is the number of attributes.

Revisión actual del 18:14 2 nov 2019

índice símbolo fórmula
SMC (concordancia simple) S (a + d)/(a + b + c + d)
Jaccard J a/(a + b + c)
Czekanovski C 2a/(2a + b + c)
Russell & Rao R a/(a + b + c + d)
distancia euclidiana (disimilaridad) ? [?(xAi - xBi)2]½


as =

a = ssp comunes
b = exclusivas de grupo 1
c = exclusivas de grupo 2
d = spp ausentes en común


The simple matching coefficient (SMC) or Rand similarity coefficient is a statistic used for comparing the similarity and diversity of sample sets.[1]

A 0 1 B 0 {\displaystyle M_{00}}M_{00} {\displaystyle M_{10}}M_{10} 1 {\displaystyle M_{01}}M_{01} {\displaystyle M_{11}}M_{11} Given two objects, A and B, each with n binary attributes, SMC is defined as:

{\displaystyle {\begin{aligned}{\text{SMC}}&={\frac {\text{number of matching attributes}}{\text{number of attributes}}}\\[8pt]&={\frac {M_{00}+M_{11}}{M_{00}+M_{01}+M_{10}+M_{11}}}\end{aligned}}}{\displaystyle {\begin{aligned}{\text{SMC}}&={\frac {\text{number of matching attributes}}{\text{number of attributes}}}\\[8pt]&={\frac {M_{00}+M_{11}}{M_{00}+M_{01}+M_{10}+M_{11}}}\end{aligned}}} where:

{\displaystyle M_{11}}M_{11} is the total number of attributes where A and B both have a value of 1. {\displaystyle M_{01}}M_{01} is the total number of attributes where the attribute of A is 0 and the attribute of B is 1. {\displaystyle M_{10}}M_{10} is the total number of attributes where the attribute of A is 1 and the attribute of B is 0. {\displaystyle M_{00}}M_{00} is the total number of attributes where A and B both have a value of 0. The simple matching distance (SMD), which measures dissimilarity between sample sets, is given by {\displaystyle 1-{\text{SMC}}}{\displaystyle 1-{\text{SMC}}}.[2]

SMC is linearly related to Hamann similarity: {\displaystyle SMC=(Hamann+1)/2}{\displaystyle SMC=(Hamann+1)/2}. Also, {\displaystyle SMC=1-D^{2}/n}{\displaystyle SMC=1-D^{2}/n}, where {\displaystyle D^{2}}D^{2} is the squared Euclidean distance between the two objects (binary vectors) and n is the number of attributes.