Study text: "Essential Mathematics and Statistics for Science", 2nd Edition,

G Currell & A A Dowman, Wiley-Blackwell, 2009

G Currell & A A Dowman, Wiley-Blackwell, 2009

- Four analysts, A, B, C and D, each prepared five replicate samples to measure the
*pH*of a specific sample of soil. The four sets of results are shown diagrammatically below:**Check all statements that are TRUE:**

(Click here for the Video Answer) - Four analysts, A, B, C and D, each prepared five replicate samples to measure the
*pH*of a specific sample of soil. The four sets of results are shown diagrammatically below:**Check all statements that are TRUE:**

(Click here for the Video Answer) - It is possible to use
*t*-tests and*F*-tests in statistics to test for significant differences in bias and precision respectively between two sets of replicate measurements.

To perform these tests, computers calculate a*p*-value, and we accept that there is a**significant**difference between data sets**if the**.*p*-value is less than 0.05

Consider the following data sets for measurement of pH:**Check all statements that are TRUE:**

(Click here for the Video Answer) - The performance specifications of an automated pipette delivering 10 mL are quoted as

If this pipette is used many times (say 1000), thenTolerance (accuracy): 0.10 mL (1%) Precision: 0.02 mL (0.2%) **which of the following statements will be true**about the volumes delivered?

(Click here for the Video Answer) - A group of
**30**students all perform**4**measurements of the same experimental value, which has a true value of 24.6. They use a method which is known to have an inherent random uncertainty which results in a random spread of values given by a standard deviation of 1.2.

Each student works out the**mean**(average) value of his/her**4**measurements.**Which statements will be true**about the 30**mean**values of 4 measurements each:

(Click here for the Video Answer) - A specific analytical procedure is known to have a standard deviation uncertainty of 0.6. A particular analysis repeats the procedure 9 times and obtains the mean result of 15.6.

Assuming that there are no systematic errors,**which of the following**would be acceptable expressions of the overall result?

(Click here for the Video Answer)