在R中进行最近邻匹配时，是否可以查看哪些case与哪些control匹配的identity? [英] When performing nearest neighbour matching in R, is it possible to view the identity of which cases matched with which controls?

问题描述

我首先在 R Studio 中尝试使用此处找到的小型练习数据集(584 个 obs，5 个变量)(https://scholarworks.umass.edu/cgi/viewcontent.cgi?article=1330&context=pare)

I'm first trying this out in R Studio with a small practice dataset found here (584 obs, 5 variables) (https://scholarworks.umass.edu/cgi/viewcontent.cgi?article=1330&context=pare)

使用此代码，我可以使用最近邻匹配来查找匹配案例和控件中的平均差异 (1:1)，其中 stw 是我的分组变量，tot、min 和 dis 是匹配变量:

Using this code I can use nearest neighbor matching to find the mean difference in matched cases and controls (1:1) where stw is my grouping variable and tot, min, and dis are the matching variables:

m.out = matchit(stw ~ tot + min + dis,
                data = mydata, method = "nearest",
                ratio = 1)

我想知道的是如何查看哪些案例与哪些控件匹配(即向我显示确切身份)?

what I want to know is how can I view which cases have matched with which controls (i.e. shows me the exact identity)?

我还想在匹配 5 个最近的邻居(即比率 = 5)并查看这些确切身份的情况下执行此操作.是否需要额外的代码?

I would also like to do this where I match 5 nearest neighbors (i.e. ratio = 5) and also view those exact identities. is there additional code needed for this?

非常感谢

推荐答案

匹配中的单位标识存储在 matchit 输出的 match.matrix 组件中目的.这是一个矩阵，行数与处理单元数相同，列数与ratio 列数相同.每行对应一个处理单元，行中的值对应于与该处理单元匹配的控制单元的身份.下面是一个例子:

The identity of units within a match are stored in the match.matrix component of the matchit output object. This is a matrix with as many rows as there are treated units and with ratio columns. Each row corresponds to a treated unit, and the values in the row correspond to the identity of the control unit matched to that treated unit. Below is an example:

> head(m$match.matrix)
     1         2        
NSW1 "PSID305" "PSID369"
NSW2 "PSID198" "PSID273"
NSW3 "PSID333" "PSID282"
NSW4 "PSID400" "PSID92" 
NSW5 "PSID426" "PSID262"
NSW6 "PSID391" "PSID261"

处理单元NSW1与控制单元<​​code>PSID305和PSID369相匹配.如果原始数据集没有行名称，则值对应于数据集中出现相应单元的行.

Treated unit NSW1 is matched with control units PSID305 and PSID369. If the original dataset did not have row names, the values correspond to the row of the dataset where the corresponding unit appears.

这篇关于在R中进行最近邻匹配时，是否可以查看哪些case与哪些control匹配的identity?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！