Verifying the feasibility of using Hand-Held X-ray fluorescence spectrometer to analyze Linqing brick: evaluation of the influencing factors and assessing reliability

Heritage Science

Table 1 Criteria for characterizing data quality (US EPA)

Data quality level	Statistical requirement
Definitive Q3	R² = 0.85–1. Relative standard deviation (RSD) ≤ 10%. Inferential statistics (test for gradient of line = 1 and y-intercept = 0) must indicate the two datasets are statistically similar (at the 95% confidence level), i.e., relationship y = x accepted
Quantitative screening Q2	R² = 0.70–1. Relative standard deviation (RSD) < 20%. Inferential statistics indicate the two datasets are statistically different; i.e., relationship y = mx or y = mx + c accepted
Qualitative screening Q1	R² = less than 0.70. Relative standard deviation (RSD) > 20%. Inferential statistics indicate that two datasets are statistically different