Determination of Weight Variation in Samples

APPLICATION OF STATISTICAL CONCEPTS IN THE DETERMINATION OF WEIGHT VARIATION IN SAMPLES

TL. A. ROSAL

DEPARTMENT OF MINING, METALLURGICAL AND MATERIALS ENGINEERING, COLLEGE OF ENGINEERING

UNIVERSITY OF THE PHILIPPINES, DILIMAN QUEZON CITY, PHILIPPINES

date performed: NOVEMBER 19, 2013

instructor’s name: KAYE CARILLO

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results and discussion

In the experiment, ten one-peso coins are used as samples. The 10 samples have the same year of coinage to lessen the error. These are cleansed beforehand. Each weight is measured using the analytical balance and weighed by difference. The analytical balance has the tolerance of ±0.0002 grams. Two Data Sets are set up. All values are recorded in Table 1.

Table 1. Recorded Weights

SAMPLE | WEIGHTS | | |

1 | 5.3592 | DATA SET 2 | DATA SET 1 |

2 | 5.3651 | | |

3 | 5.3494 | | |

4 | 5.3562 | | |

5 | 5.3832 | | |

6 | 5.374 | | |

7 | 5.2829 | | |

8 | 2.2849 | | |

9 | 5.3393 | | |

10 | 5.3194 | | |

The calculated values for the mean standard deviation, relative standard deviation, the range, relative range and confidence limits are listed on Table 2.

Table 2. Reported Values

PARAMETERS | DATA SET 1 | DATA SET 2 |

X | 5.3645 ± 0.0005 | 5.3414 ± 0.0006 |

S | 0.01237 | 0.03508 |

RSD | 2.3059 | 6.5676 |

R | 0.0338 ± 0.0003 | 0.1003 ± 0.0003 |

RR | 6.30 ± 0.056 | 18.8 ± 0.056 |

CL | 5.3645 ± 0.013 | 5.3414 ± 0.0250 |

Standard deviation is the measure of how closely replicate data cluster around the mean. A low standard deviation indicates that the data points tend to be very close to the mean, whereas high standard deviation indicates that the data is spread out over a large range of values [1].

The computed standard deviation, listed on Table 2, is relatively low for both data sets which indicate that the weights tend to be very close to the mean.

A...