In earlier work, August et al. (2022) evaluated three different Natural Language Generation systems on their ability to generate fluent, relevant, and factual scientific definitions. As part of the ReproHum project (Belz et al., 2023), we carried out a partial reproduction study of their human evaluation procedure, focusing on human fluency ratings. Following the standardised ReproHum procedure, our reproduction study follows the original study as closely as possible, with two raters providing 300 ratings each. In addition to this, we carried out a second study where we collected ratings from eight additional raters and analysed the variability of the ratings. We successfully reproduced the inferential statistics from the original study (i.e. the same hypotheses were supported), albeit with a lower inter-annotator agreement. The remainder of our paper shows significant variation between different raters, raising questions about what it really means to reproduce human evaluation studies.

This paper is part of the larger ReproHum project, where different teams of researchers aim to reproduce published experiments from the NLP literature. Specifically, ReproHum focuses on the reproducibility of human evaluation studies, where participants indicate the quality of different outputs of Natural Language Generation (NLG) systems. This is necessary because without reproduction studies, we do not know how reliable earlier results are. This paper aims to reproduce the second human evaluation study of Puduppully & Lapata (2021), while another lab is attempting to do the same. This experiment uses best-worst scaling to determine the relative performance of different NLG systems. We found that the worst performing system in the original study is now in fact the best performing system across the board. This means that we cannot fully reproduce the original results. We also carry out alternative analyses of the data, and discuss how our results may be combined with the other reproduction study that is carried out in parallel with this paper.

In this paper, we describe our reproduction ef- fort of the paper: Towards Best Experiment Design for Evaluating Dialogue System Output by Santhanam and Shaikh (2019) for the 2022 ReproGen shared task. We aim to produce the same results, using different human evaluators, and a different implementation of the automatic metrics used in the original paper. Although overall the study posed some challenges to re- produce (e.g. difficulties with reproduction of automatic metrics and statistics), in the end we did find that the results generally replicate the findings of Santhanam and Shaikh (2019) and seem to follow similar trends.