The phenomenon where axis ticks appear smaller or reduced in size in plots saved using the `ggsave` function in R, compared to their on-screen display, is a common issue related to resolution and scaling. Specifically, the default settings of `ggsave` may result in saved images having a different resolution than the display resolution, leading to a discrepancy in the visual size of plot elements, including axis ticks. For example, a plot viewed on screen with legible axis ticks may, after saving via `ggsave` without specifying dimensions or resolution, exhibit noticeably smaller and potentially less legible ticks in the saved image file.
This issue is important because it impacts the clarity and readability of visualizations, particularly for publications or presentations where image quality is crucial. Correctly sized axis ticks are essential for conveying quantitative information accurately. Historically, users have encountered this problem due to variations in default settings across different R versions and graphics devices. Furthermore, the increasing use of high-resolution displays exacerbates the issue, as plots optimized for those screens may appear significantly smaller when saved using lower default resolutions.
