I am doing Ordinary Kriging analysis on PM10 (air pollutants) concentrations dataset. This dataset contains hourly PM10 concentrations of 3 months (3X30X24) for 83 observation stations. Minimum and maximum distance among stations are 500 m and 60 km respectively.
I have performed Ordinary Kriging interpolation (using gstat package in R) on each hourly dataset for first 2 days and after cross validation(leave one out) I checked the following statistical parameter between observed values and predicted values:
Mean Bias/Mean Error = -0.20 to +0.20
Mean Normalized Bias(MNB) =2.44% to 56%
Mean Normalized Gross Error (MNGE) = 12.78% to 78.2%
RMSE = 8 to 24
Correlation Coefficient (R) = 0.18 to 0.72
Average observed PM10 concentrations = 17.43 to 78.70 microgram/m3
I noticed that statistical parameters varying in a large range. Based on these parameters can I say , Kriging interpolation is satisfactory for this dataset? Should I calculate any other statistical parameters?
Could you please discuss this issue in detail? (To evaluate the performance of Ordinary Kriging, Which parameters I should check and why?)
[I am attaching bar plots of every statistical parameters between observed values and predicted valued for 48 hours]