How Does Visibility Count? An Open Data-Driven Approach to Compare the Use of Ground Visibility in Archaeological Field-Walking Surveys in the Mediterranean Region

There is a common agreement among archaeologists that assessing visibility in the field is essential to measure the accuracy of their observations. Archaeologists widely expect that low visibility negatively impacts the recovery rate of artefacts and sites during field-walking surveys. However, they hold fundamentally divergent opinions on using recorded visibility values and on whether or how to weight the results. In this paper, I undertake a review and comparison of ground visibility assessments from three archaeological field-walking surveys conducted in the eastern Mediterranean, all of which have published their data. Capitalizing on the availability of open data, I recode and analyse the algorithms employed in these surveys. The results highlight the impacts of weighting techniques, and I compare the maps produced with and without weighting. In all cases, the corrections do not substantially change the interpretations of the results at the scale of site identification. As such, this data-driven experiment contributes to the ongoing debate on how to compare effectively and integrate data from various survey projects to study regional trends.