Fig. 2

Median correction of colony sizes reduces the influence of plate differences. A External factors and discrepancies in pinning can result in differences in colony growth between plates. The mean LGRs organised by plate without median correction are plotted. B Correction of colony sizes using the plate median counteracts these plate differences, median correction data from A is plotted. C A heatmap shows spatial anomalies of colony sizes on plate especially at the plate periphery. Red squares indicate a colony size greater than the plate median and blue squares highlight smaller colonies. The inset shows an example of the raw data. D–F Mean LGRs are plotted against the yeast library with the data organised on the x-axis, by plate, row and column to highlight the impact of plate differences and spatial anomalies. Including the spatial smoothing algorithm further abolishes any differences based on colony position on plate