是否有R函数来获取预期计数表？

Question

我有下表的胃灼热症状和对两种不同药物的反应:

           Medication
Symptoms    Drug A Drug B Totals
  Heartburn     64     92    156
  Normal       114     98    212
  Totals       178    190    368

我正在寻找一个R函数,它通过以下操作来获得预期的计数:

                    Medication
Symptoms       Drug A                   Drug B               
Heartburn     156 * 178 / 368 = 75      156 * 190 / 368 = 81 
Normal        212 * 178 / 368 = 103     212 * 190 / 368 = 109

理想情况下,显示器甚至可选择如下:

           Medication
Symptoms       Drug A   Drug B    Totals
  Heartburn     64(75)   92(81)    156
  Normal       114(103)  98(109)   212
  Totals       178      190        368

这不是太多问,是吗？

Answer 1

示例来自?chisq.test:

 M <- as.table(rbind(c(762, 327, 468), c(484, 239, 477)))
 dimnames(M) <- list(gender = c("F", "M"),
                     party = c("Democrat","Independent", "Republican"))
 Xsq <- chisq.test(M)  # Prints test summary

我认为$expected结果的组成部分是你想要的:

 Xsq$expected
 ##       party
 ## gender Democrat Independent Republican
 ##      F 703.6714    319.6453   533.6834
 ##      M 542.3286    246.3547   411.3166

您首选显示的开头:

M2 <- M; 
M2[] <- paste(M,paste0("(",round(Xsq$expected),")"))
##      party
## gender Democrat  Independent Republican
##      F 762 (704) 327 (320)   468 (534) 
##      M 484 (542) 239 (246)   477 (411) 

也可以看看 ?addmargins