Examples of time series of 193 Å intensities (top) and corresponding probability density functions (PDFs; bottom) for single-pixel signals in the CH1 and QS1 regions. (Left) A pixel in the coronal hole; (right) a pixel in the neighboring quiet-Sun region. The mean, kurtosis and skewness of the PDFs are: 16.0, 3.12, 0.18 (CH); 81.9, 2.55, 0.32 (QS).