prop_trend_test {rstatix} | R Documentation |
Test for Trend in Proportions
Description
Performs chi-squared test for trend in proportion. This test is also known as Cochran-Armitage trend test.
Wrappers around the R base function prop.trend.test()
but
returns a data frame for easy data visualization.
Usage
prop_trend_test(xtab, score = NULL)
Arguments
xtab |
a cross-tabulation (or contingency table) with two columns and multiple rows (rx2 design). The columns give the counts of successes and failures respectively. |
score |
group score. If |
Value
return a data frame with some the following columns:
-
n
: the number of participants. -
statistic
: the value of Chi-squared trend test statistic. -
df
: the degrees of freedom. -
p
: p-value. -
method
: the used statistical test. -
p.signif
: the significance level of p-values and adjusted p-values, respectively.
The returned object has an attribute called args, which is a list holding the test arguments.
Examples
# Proportion of renal stone (calculi) across age
#%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
# Data
xtab <- as.table(rbind(
c(384, 536, 335),
c(951, 869, 438)
))
dimnames(xtab) <- list(
stone = c("yes", "no"),
age = c("30-39", "40-49", "50-59")
)
xtab
# Compare the proportion of survived between groups
prop_trend_test(xtab)