APPLICATION OF STATISTICAL CONCEPTS IN THE DETERMINATION OF WEIGHT VARIATION IN SAMPLES
APPLICATION OF STATISTICAL CONCEPTS IN THE DETERMINATION OF WEIGHT VARIATION IN SAMPLES
M.C. MENDOZA1
1NATIONAL INSTITUTE OF MOLECULAR BIOLOGY & BIOTECHNOLOGY, COLLEGE OF SCIENCE
UNIVERSITY OF THE PHILIPPINES, DILIMAN, QUEZON CITY 1101, PHILIPPINES
DATE SUBMITTED: 21 NOVEMBER 2013
DATE PERFORMED: 14 NOVEMBER 2013
ABSTRACT
Accuracy and precision are critical concepts to the performance of a laboratory to produce sound analytical results (Singer, 2001). LOLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL
RESULTS AND DISCUSSION
The analytical balance was used in this experiment to determine the weight of each 25 centavo coin. This was done by performing the weighing by difference method. Results were then recorded in table 1.
Table 1 below shows the weight of the ten samples of coins. The samples were then divided into two data sets; samples 1-6 (data set 1) and samples 1-10 (data set 2).
Table 1.Weight of 25 centavo coin samples
Sample No.
Weight, g
1
3.5800
Data Set 2
Data Set 1
2
3.6073
3
3.5904
4
3.6140
5
3.5940
6
3.6265
7
3.6016
8
3.7603
9
3.5974
10
3.5978
Since this experiment aims to apply some statistical concepts in analytical chemistry, statistical tests were done in order to assess both precision and accuracy of the data gathered.
However in an experiment, it is possible that some of the data gathered can be considered invalid. These outliers are usually the highest or the lowest value in a set of data which differ significantly from the other observations. In presence of which, some statistics, like the mean, are greatly affected especially if there is a small number of observations. Hence, for this experiment to have accurate and precise conclusions, a test for detecting outliers must first be performed before proceeding with the analysis. The Dixon’s Q-test is one of the most commonly used test where in Qexperimental (1) is calculated and compared with
M.C. MENDOZA1
1NATIONAL INSTITUTE OF MOLECULAR BIOLOGY & BIOTECHNOLOGY, COLLEGE OF SCIENCE
UNIVERSITY OF THE PHILIPPINES, DILIMAN, QUEZON CITY 1101, PHILIPPINES
DATE SUBMITTED: 21 NOVEMBER 2013
DATE PERFORMED: 14 NOVEMBER 2013
ABSTRACT
Accuracy and precision are critical concepts to the performance of a laboratory to produce sound analytical results (Singer, 2001). LOLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL
RESULTS AND DISCUSSION
The analytical balance was used in this experiment to determine the weight of each 25 centavo coin. This was done by performing the weighing by difference method. Results were then recorded in table 1.
Table 1 below shows the weight of the ten samples of coins. The samples were then divided into two data sets; samples 1-6 (data set 1) and samples 1-10 (data set 2).
Table 1.Weight of 25 centavo coin samples
Sample No.
Weight, g
1
3.5800
Data Set 2
Data Set 1
2
3.6073
3
3.5904
4
3.6140
5
3.5940
6
3.6265
7
3.6016
8
3.7603
9
3.5974
10
3.5978
Since this experiment aims to apply some statistical concepts in analytical chemistry, statistical tests were done in order to assess both precision and accuracy of the data gathered.
However in an experiment, it is possible that some of the data gathered can be considered invalid. These outliers are usually the highest or the lowest value in a set of data which differ significantly from the other observations. In presence of which, some statistics, like the mean, are greatly affected especially if there is a small number of observations. Hence, for this experiment to have accurate and precise conclusions, a test for detecting outliers must first be performed before proceeding with the analysis. The Dixon’s Q-test is one of the most commonly used test where in Qexperimental (1) is calculated and compared with