[問題] 如何使matrix中的數值小數位不要進位

[Inderal10mg (Propranolol)]

[問題類型]:

程式諮詢(我想用R 做某件事情，但是我不知道要怎麼用R 寫出來)


[軟體熟悉度]:

入門


[問題敘述]:

使用package"exact2x2"執行Exact McNemar's test時，因細格中有零，
按照文獻建議各加0.5才執行計算，但是r會將0.5視為0，想請教前輩們如何
讓其維持在0.5的狀態下計算Odds ratio與95% confidence interval，謝謝。


[程式範例]:

# 使用套件
library(exact2x2)

# 輸入計算數值
x=matrix(c(18.5,13.5,0.5,4.5),2,2)

#計算結果
mcnemar.exact(x)

#結果
Exact McNemar test (with central confidence intervals)

data:  x
b = 0, c = 14, p-value = 0.0001221
alternative hypothesis: true odds ratio is not equal to 1
95 percent confidence interval:
 0.0000000 0.3014661
sample estimates:
odds ratio
         0

Warning message:
In exact2x2(x = x, alternative = "two.sided", tsmethod = "central",  :
  'x' has been rounded to integer: Mean relative difference: 0.05405405


[環境敘述]:

R version 3.5.3 (2019-03-11)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 10 x64 (build 17763)

Matrix products: default

locale:
[1] LC_COLLATE=Chinese (Traditional)_Taiwan.950
[2] LC_CTYPE=Chinese (Traditional)_Taiwan.950
[3] LC_MONETARY=Chinese (Traditional)_Taiwan.950
[4] LC_NUMERIC=C
[5] LC_TIME=Chinese (Traditional)_Taiwan.950

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base

other attached packages:
[1] exact2x2_1.6.3 exactci_1.3-3  ssanv_1.1

loaded via a namespace (and not attached):
[1] compiler_3.5.3


[關鍵字]:

exact2x2, exact mcnemar test


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→ andrew43: 這個例子，加0.6就可以解決。但你都用exact了需要靠加
→ andrew43: 更正。它會自動round，且你都用exact需要靠加0.5修正嗎?
→ andrew43: 這種修正是傳統上採近似分布才需要的吧?
→ andrew43: exact方法先了解一下就會明白資料一定只能是整數。
→ Inderal10mg: 謝謝，想知道有辦法讓它不要自動round嗎?
→ Inderal10mg: 我用?mcnemar.exact查詢找不到可以調整的地方
→ Inderal10mg: 因為要算odds ratio所以必須要加0.5修正zero count
→ andrew43: 你說的odds ratio應該只是0.5/13.5，手算即可。
→ Inderal10mg: 感謝