Figure 4

The Q-Q plot of the quantiles of the baseline signal versus the quantiles of a standard normal distribution. A Q-Q plot is a probability plot for comparing two probability distributions by plotting their quantiles against each other. The Q-Q plot shown in this figure approximately lies on a line, indicating that the distribution of the baseline noise and the Gaussian distribution are linearly related, so the baseline noise in this work was simulated as white Gaussian noise with different scales.