[Question]: Can I know a weighting factor and how it is calculated? Can it be adjusted?

[3Stoness]

Can I know a weighting factor and how it is calculated? Can it be adjusted?
filter(traj, lon > -20, lon < 20, lat > 45, lat < 60) %>%
trajLevel(
pollutant = "pm2.5", statistic = "pscf",
col = "increment",
border = NA
)
"Note also that cells with few data have a weighting factor applied to reduce their effect."（ https://bookdown.org/david_carslaw/openair/sections/directional-analysis/trajectory-analysis.html#potential-source-contribution-function-pscf 10.5 Potential Source Contribution Function (PSCF)）