大學化學專業(yè)——————最詳細的數(shù)據及誤差分析誤差ppt

1、Error and Data Handling 53-5-5. Rejection of A Result Frequently, when a series of replicate analyses are performed, one of the results will appear to differ markedly from the other. A decision will have to be made whether to reject the result or to retain it.2022/7/2121. Q test(1) Arrange the resul

2、ts in order from the lowest to the highest, such as (2) Calculate the difference between the maximum and minimum values (range, R), (3) Find the difference between the questionable result and its nearest neighbor, 2022/7/213(4) The rejection quotient Qc is calculated from the equation;(5) Consult th

3、e table3-3, find the Qt from a table of statistical constants. If , the result can be discarded.If , the result should be retained.2022/7/214Example 1測定水中砷的含量，3次測定結果分別為1mg/L, 2mg/L, 9mg/L.問可疑數(shù)據“9”應否棄去(P=0.90)?查表3-3得 因 故9mg/L這一數(shù)值不應棄去 Critical values for the Rejection Quotient, Q值表2022/7/215Example 2T

4、he following set of chloride analyses on separate aliquots of a pooled serum were reported. One value appears suspect. Determine if it can be ascribed to accidental error. 103, 106, 107, 114meq/liter.SolutionThe suspected number may not be rejected2022/7/2162.G (Grubbs) test Calculate the mean of th

5、e results and the standard deviation s Calculate the Gcvalue Consult the table, find the Gt Arrange the result from the lowest to the highest(correspond to certain confidence level)2022/7/217If GcCt, the result can be discarded.If GcCt, the result should be retained.In Grubbs test, not only set up certain confidence level, But also introduce the mean and standard deviation, so its accuracy is better than of Q test.2022/7/218有一組測定值為73.5, 69.5, 69.