| Type: | Package |
| Title: | A Nonparametric Trend Test for Independent and Dependent Samples |
| Version: | 0.1.0 |
| Description: | Implements the nonparametric trend test for one or several samples as proposed by Bathke (2009) <doi:10.1007/s00184-008-0171-x>. The method provides a unified framework for analyzing trends in both independent and dependent data samples, making it a versatile tool for various study designs. The package allows for the evaluation of different trend alternatives, including two-sided (general trend), monotonic increasing, and monotonic decreasing trends. As a nonparametric procedure, it does not require the assumption of data normality, offering a robust alternative to parametric tests. |
| License: | MIT + file LICENSE |
| Encoding: | UTF-8 |
| Depends: | R (≥ 3.5.0) |
| Imports: | stats |
| Suggests: | testthat |
| RoxygenNote: | 7.3.2 |
| NeedsCompilation: | no |
| Packaged: | 2025-07-21 12:33:12 UTC; shekh |
| Author: | Daria Suraeva [aut, cre] |
| Maintainer: | Daria Suraeva <dariastime@gmail.com> |
| Repository: | CRAN |
| Date/Publication: | 2025-07-22 11:20:43 UTC |
Nonparametric Trend Test (Bathke, 2009)
Description
Performs a nonparametric trend test for independent or dependent samples based on Bathke (2009).
Usage
nonparTrendR_test(data, type = c("I", "D"), alternative = NULL)
Arguments
data |
For 'type = "I"' (independent samples), a list of numeric vectors, where each vector represents a group. For 'type = "D"' (dependent samples), a numeric matrix where rows are subjects and columns are conditions/time points (ordered by the expected trend). |
type |
A character string specifying the type of data: '"I"' for independent samples (uses Formula 2 from Bathke, 2009). '"D"' for dependent samples (uses Formula 4 from Bathke, 2009, for an increasing trend). |
alternative |
A character string specifying the alternative hypothesis, must be one of '"two.sided"' (default for independent), '"increasing"' (default for dependent), or '"decreasing"'. |
Value
A list with class '"htest"' containing the following components:
statistic |
The value of the test statistic ( |
p.value |
The p-value for the test. |
alternative |
A character string describing the alternative hypothesis. |
method |
A character string indicating the type of test performed. |
data.name |
A character string giving the name(s) of the data. |
References
Bathke, A. C. (2009). A unified approach to nonparametric trend tests for dependent and independent samples. *Metrika*, 69(1), 17-29.
Examples
# --- Independent Samples Example (Table 2 from paper) ---
group1_indep <- c(6.62, 6.65, 5.78, 5.63, 6.05, 6.48, 5.50, 5.37)
group2_indep <- c(6.25, 6.95, 5.61, 5.40, 6.89, 6.24, 5.85)
group3_indep <- c(7.11, 5.68, 6.23, 7.11, 5.55, 5.90, 5.98, 7.14)
group4_indep <- c(6.93, 7.17, 7.12, 6.43, 6.96, 7.08, 7.93)
group5_indep <- c(7.26, 6.45, 6.37, 6.54, 6.93, 6.40, 7.01, 7.74, 7.63, 7.62, 7.38)
data_independent <- list(group1_indep, group2_indep, group3_indep, group4_indep, group5_indep)
nonparTrendR_test(data_independent, type = "I", alternative = "increasing")
# --- Dependent Samples Example (Panic Data from paper) ---
panic_data_dep <- matrix(c(
8, 6, 5, 5, 4, 8, 6, 5, 4, 2, 6, 5, 5, 4, 2, 6, 6, 6, 5, 5,
7, 6, 6, 6, 6, 8, 7, 3, 2, 2, 7, 6, 7, 3, 3, 6, 4, 5, 3, 3,
5, 4, 3, 3, 2, 8, 6, 5, 5, 4, 7, 6, 5, 4, 2, 6, 5, 5, 4, 2,
6, 6, 6, 5, 5, 8, 6, 6, 6, 6, 8, 7, 4, 2, 2, 7, 6, 7, 3, 3
), nrow = 16, byrow = TRUE)
# For increasing trend test, data should be ordered such that higher values are expected later.
# If testing for decreasing trend as in your example,
# reverse the columns or use alternative="decreasing"
# Example using original order, testing for decreasing:
nonparTrendR_test(panic_data_dep, type = "D", alternative = "decreasing")
# Example reversing columns to test for increasing trend of "improvement"
nonparTrendR_test(panic_data_dep[, 5:1], type = "D", alternative = "increasing")