Contents
Key Stage 4
Meaning
Results are precise if the same reading or measurement repeatedly gives a similar value.
About Precision
- The smaller the range and uncertainty the greater the precision.
- Precision is achieved by controlling variables so that readings are stable over a long period of time.
- An readings can be made more precise by removing sources of random error.
Accuracy vs Precision
| Method | Test 1 | Test 2 | Test 3 | Average | Range |
| Method 1 | 3.27 | 3.09 | 3.01 | 3.12 | 0.26 |
| Method 2 | 3.91 | 3.88 | 3.88 | 3.89 | 0.03 |
| Method 3 | 3.57 | 2.89 | 2.93 | 3.13 | 0.68 |
Method 1: The most accurate measurements because they are the closest to pi but they are not very precise because they have a range of 0.26. Method 2: These are the least accurate measurements because they are the furthest from pi but they are very precise because they have a range of only 0.03. Method 3: Each measurement is not accurate because they are far from pi, they are also the least precise because they have a range of 0.68. However, the average is the most accurate as it is the closes to pi. | |||||
References
AQA
- Precision (of results), page 5, GCSE Biology; The Revision Guide, CGP, AQA
- Precision, page 12, GCSE Chemistry, CGP, AQA
- Precision, page 12, GCSE Combined Science Trilogy; Chemistry, CGP, AQA
- Precision, page 148, GCSE Biology, Hodder, AQA
- Precision, page 274, GCSE Chemistry, Hodder, AQA
- Precision, page 289, GCSE Combined Science Trilogy 1, Hodder, AQA
- Precision, page 34, GCSE Physics, Hodder, AQA
- Precision, page 5, GCSE Combined Science; The Revision Guide, CGP, AQA
- Precision, page 5, GCSE Physics; The Revision Guide, CGP, AQA
- Precision, page 6, GCSE Chemistry; The Revision Guide, CGP, AQA
- Precision, pages 10, 204, GCSE Combined Science Trilogy 2, Hodder, AQA
- Precision, pages 105, 286, GCSE Chemistry; Student Book, Collins, AQA
- Precision, pages 266-267, GCSE Chemistry; Third Edition, Oxford University Press, AQA
- Precision, pages 279-280, GCSE Physics; Third Edition, Oxford University Press, AQA
Edexcel
- Precision, page 12, GCSE Chemistry, CGP, Edexcel
- Precision, page 5, GCSE Combined Science; The Revision Guide, CGP, Edexcel
- Precision, page 6, GCSE Biology; The Revision Guide, CGP, Edexcel
- Precision, page 6, GCSE Chemistry; The Revision Guide, CGP, Edexcel
- Precision, page 6, GCSE Physics; The Revision Guide, CGP, Edexcel
OCR
- Precision, page 5, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR
- Precision, page 6, Gateway GCSE Biology; The Revision Guide, CGP, OCR
- Precision, page 6, Gateway GCSE Chemistry; The Revision Guide, CGP, OCR
- Precision, pages 10, 11, 167, Gateway GCSE Chemistry, Oxford, OCR
Key Stage 5
Meaning
Results are precise if the same reading or measurement repeatedly gives a similar value.
About Precision
- A single reading may be more precise if the resolution of the measuring instrument is higher. This is due to the upper and lower bounds of a single number being smaller when the number has a greater resolution. A ruler that measures to the nearest 1cm has an uncertainty of ±5mm for each reading. A ruler that measures to the nearest 1mm has an uncertainty of ±0.5mm, making a single reading more precise.