This preview shows page 1. Sign up to view the full content.
Unformatted text preview: for all experimental collections of data. The formula to do
this is: Confidence Limit = t
N where t varies with the number of observations. For the 90% confidence limits
you are asked to calculate, t = 6.314 when N = 2, t = 2.920 when N = 3, t = 2.353
when N = 4, t = 2.132 when N = 5, and t = 2.015 when N = 6. You should always
report your result as the average ± the 90% confidence limit.
Relative Deviation
The relative average deviation, d, like the standard deviation, is useful to
determine how data are clustered about a mean. The advantage of a relative
deviation is that it incorporates the relative numerical magnitude of the average.
The relative average deviation, d, is calculated in the following way.
a) Calculate the average, x, with all data that are of high quality.
b) Calculate the deviation, xi  x, of each good piece of data.
c) Calculate the average of these deviations.
d) Divide that average of the deviations by the mean of the good data.
This number is generally expressed as parts per thousand (ppt). You can do this
by simply multiplying by 1000.
Please report the relative avera...
View
Full
Document
This note was uploaded on 04/09/2013 for the course CHE CHE 2C taught by Professor Nasiri during the Spring '07 term at UC Davis.
 Spring '07
 Nasiri
 Chemistry

Click to edit the document details