# Contingency Table: Proportions between two Choices differ, p-Value of 1?

I have survey data, where participants where asked to choose two times between yes and no For this example let's say (although I am note quite sure if this is a good example).

1. Choice1: Do you want to take to be acknowledge by your coworkers?
2. Choice2: Do you want to be responsible if something goes wrong?

So now we found considerable differences in the amount of yes and no to the two questions.

pacman::p_load(tidyverse)
# MRE Data
> df
Choice2
Choice1 No Yes
No   6   1
Yes 22   6

# dput
structure(c(6L, 22L, 1L, 6L), .Dim = c(2L, 2L), .Dimnames = list(
Choice1 = c("No", "Yes"), Choice2 = c("No", "Yes")), class = "table")


I am interested if these diferences are significant. So if e.g. substantially more participants chose yes for Choice1 then for Choice2. I thought I could analyze this with a $$\chi^2$$ Test?

However due to the small sample (and the small expected cell count) I got a warning, from chisq.test, so instead I conducted a Fisher's exact test.

# Chi² Test of Independence
chi <- chisq.test(df)
chi
# Exepected Cell Count
chi$expected # Due to small expected cell count and Warning: Chi-squared approximation may be incorrect # Instead conduct a fisher exact test fisher.test(df) Fisher's Exact Test for Count Data data: df p-value = 1 alternative hypothesis: true odds ratio is not equal to 1 95 percent confidence interval: 0.1437625 87.6035655 sample estimates: odds ratio 1.615585  What strikes me about the result is a p value of 1. Looking at the proportions for Choice 1 80% voted no, for Choice 2 20%. This appears to be reasonable differences. # Print proportions df %>% rbind("Prop" =(prop.table(df) %>% colSums() *100)) %>% cbind("Prop" = c((prop.table(df) %>% rowSums() *100),100)) # Choice 1: No = 80%, Choice 2: No = 20% how is p = 1 No Yes Prop No 6 1 20 Yes 22 6 80 Prop 80 20 100  No I am wondering if I am even using the right test? I know that the $$\chi^2$$ is a test of independence. So the H1 would be that Choice1 and Choice2 are dependent. However I am rather interested in knowing if the propotions between Choice1 and Choice2 are meaningful different. And how does it come that I get a p = 1 ### Edit Created the differ Variable > df # A tibble: 35 x 3 Choice1 Choice2 differ <fct> <fct> <dbl> 1 Yes No 1 2 Yes No 1 3 Yes No 1 4 No No 0 5 No No 0 6 Yes No 1 7 Yes Yes 0 8 Yes No 1 9 Yes Yes 0 10 Yes No 1 # ... with 25 more rows > df %>% dput() structure(list(Choice1 = structure(c(2L, 2L, 2L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 1L, 2L, 2L, 2L, 2L, 2L, 1L, 2L, 2L, 1L, 2L, 2L, 2L, 2L, 2L, 1L, 2L, 2L, 1L, 2L, 2L), .Label = c("No", "Yes"), class = "factor"), Choice2 = structure(c(1L, 1L, 1L, 1L, 1L, 1L, 2L, 1L, 2L, 1L, 1L, 1L, 1L, 2L, 1L, 1L, 2L, 1L, 1L, 1L, 2L, 1L, 2L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L ), .Label = c("No", "Yes"), class = "factor"), differ = c(1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 1, 0, 1, 0)), class = c("tbl_df", "tbl", "data.frame"), row.names = c(NA, -35L))  ## Solution Edit: In addition to the provided answer, I would like to point attention to the very helpful question that @Scortchi linked in the comments (see here). The answer provided by Gung really improved my understanding and helped me navigate. The correct test for my question would be either the binominal test (as mentioned in the accepted answer) or the McNemmar $$\chi^2$$ test. Please refer to the link for more details on the reasoning behind. • Jan 28 at 17:01 • Thanks this link was extremely helpful. So if I understand @Gung corectly, in my case, where I want ot know if the number of people who voted yes differed between choice1 and chocie2, I would also want to calculate "Specifically, you want to run a within-subjects z-test of equality of proportions. That is what McNemar's test is."? As the$H_0\$ would be that the proportions are identical? Jan 28 at 17:16

• I included an edit. Yes this are the same people / participants asked twice (repeated measure). Included the variable differ, when choice 1 is differnt from choice 2. "then only people whose responses differ are informative so you need just those two numbers and then do a binomial test." Which 2 numbers do you mean? The amount (n) who differed between choice1 and choice2 (e.g., differ = 1) and those who did not (differ = 0)? Jan 28 at 16:45