Comparing Various Descriptive Statistics for Two Independent Groups in Agricultural Experiments

Year 2026, Volume: 32 Issue: 1, 130 - 144, 20.01.2026

Zeynel Cebeci , Melis Çelik Güney , Uğur Serbester

https://doi.org/10.15832/ankutbd.1727052

Abstract

Comparing two groups holds significant importance in statistical analysis across various fields, including agriculture, where performance evaluations are commonly conducted. Conventional parametric and nonparametric tests primarily focus on differences in central tendencies, often neglecting distributional variations, especially across quantiles. This study explores the potential of resampling techniques, such as bootstrapping and permutation tests, in enhancing group comparisons beyond traditional measures like means and medians. Using both simulated and real agricultural datasets, the study demonstrates how quantile-based comparisons supported by resampling methods provide deeper insights into group differences. The results highlight that relying solely on central measures can overlook substantial variations in the distributional tails, emphasizing the necessity of a comprehensive examination of quantiles. Moreover, the findings show that permutation tests, which align with classical methods for central measures, offer a robust, assumption-free alternative that captures higher-order characteristics like skewness and kurtosis. Bootstrapping with the Biascorrected and Accelerated (BCa) bootstrap confidence intervals also prove to be a reliable tool for estimating sampling distributions. A notable observation is that quantile-based comparisons can detect significant differences in distributional tails, even when conventional tests fail to identify discrepancies in medians. This underscores the power of quantile comparison in unveiling subtle yet critical differences between groups, offering a richer and more precise inferential framework. The study concludes by advocating the adoption of resampling-based quantile comparison methods in agricultural research, as they significantly enhance the detection of distributional differences and bolster the overall rigor of statistical analyses.

Keywords

Bootstrap method , Permutation tests , Quantile comparison , Resampling techniques , T-test

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