Statistical Testing for Treatment of Data

Question 1

The most common central value used
By chemists is the __________, which is obtained by dividing the
sum of the individual values by the
number of values.

Answer 1

arithmetic mean,
x

Question 2

It is the middle numerical value in a set of values

Answer 2

Median

Question 3

which is not so common in analytical chemistry, of data is the value that is most frequently repeated in the data set.

Answer 3

Mode

Question 4

refers to how closely individual measurements agree with the correct, or “true,” value.

Answer 4

Accuracy

Question 5

measure of how closely individual measurements agree with one another

Answer 5

Precision

Question 6

describes the nearness of an experimental value, xi , or a mean, to the true value,

Answer 6

accuracy

Question 7

Absolute error is calculated

Answer 7

error =xi - µ

Question 8

is used when comparing errors at different quantities

Answer 8

Relative error

Relative error =𝑒𝑟𝑟𝑜𝑟 / µ

Question 9

Relative error is often expressed by statisticians as

Answer 9

Parts per hundred (pph) or percent error is the relative
error multiplied by 100. Parts per thousand (ppt) error is
the relative error multiplied by 1000

Question 10

refers to the agreement between values in a set of data

Answer 10

Precision

Question 11

It is one of the methods of showing dispersion or way of ascertaining the deviation, taken without regard to sign, of the experimental value from the central value

Answer 11

Average deviation (or mean deviation)

Question 12

is the preferred measure of precision
and is calculated from the equation

Answer 12

Standard deviation of the sample

Question 13

is the absolute difference between the largest and smallest values in the data set

Answer 13

Range

Question 14

Another term to describe the precision of a set of replicate results.

Answer 14

Spread or Range (w)