Rielke Bogaert, Emmelien Merchie, Yves Rosseel, Hilde Van Keer
Development of the Reading Comprehension Strategies Questionnaire (RCSQ) for late elementary school students
Frontiers in psychology
east asian countries conducting source apportionment fine particulate matter pm25 applying positive matrix factorization pmf hourly constituent concentrations however constituent data supersites south korea missing due instrument maintenance calibration conventional preprocessing missing values exclusion median replacement causes biases estimated source contributions changing pmf input machine learning ml estimate missing values training constituent data meteorological data gaseous pollutants complete data seoul supersite 2018 taken random 20 set missing pmf performed replacing missing values estimates percent errors source contributions calculated compared estimated complete data missing values estimated using random forest analysis estimation accuracy r2 high 0874 missing carbon species low 0631 ionic species trace elements missing seven highest contributing sources replacing missing values carbon species estimates minimized percent errors 20 average however replacing missing values chemical species estimates increased percent errors 97 average percent errors maximal 37 average missing values ionic species trace elements replaced estimates missing values except carbon species need excluded approach reduced percent errors 74 average lower due median replacement results show reducing biases source apportionment possible replacing missing values carbon species estimates improve biases due missing values chemical species estimation accuracy ml needs improved