Difference between revisions of "Accurate"

Revision as of 09:15, 25 March 2019

Key Stage 4

Meaning

Results are accurate if they are close to the true value.

About Accuracy

Accuracy is achieved by:

Removing systematic errors from the readings.
Removing zero errors by calibrating instruments before the investigation.
Controlling all the variables except for the independent variable and the Dependent Variable.

If there are random errors and a small sample size taking repeat readings, removing anomalies and calculating an average can improve the accuracy.

If there are systematic errors or zero errors the results can be improved by finding the source of the error and correcting it.

Accuracy vs Precision

Experimental Measurements of pi
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
The number pi is 3.14159265359 correct to 12 significant figures. 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.

@@ Line 12: / Line 12: @@
 ===Accuracy vs Precision===
+{| class="wikitable"
+|+ Experimental Measurements of [[pi]]
+|-
+| style="height:20px; width:100px; text-align:center;" |'''Method'''
+| style="height:20px; width:100px; text-align:center;" |'''Test 1'''
+| style="height:20px; width:100px; text-align:center;" |'''Test 2'''
+| style="height:20px; width:100px; text-align:center;" |'''Test 3'''
+| style="height:20px; width:100px; text-align:center;" |'''Average'''
+| style="height:20px; width:100px; text-align:center;" |'''Range'''
+|-
+| style="height:20px; width:100px; text-align:center;" |Method 1
+| style="height:20px; width:100px; text-align:center;" |3.27
+| style="height:20px; width:100px; text-align:center;" |3.09
+| style="height:20px; width:100px; text-align:center;" |3.01
+| style="height:20px; width:100px; text-align:center;" |3.12
+| style="height:20px; width:100px; text-align:center;" |0.26
+|-
+| style="height:20px; width:100px; text-align:center;" |Method 2
+| style="height:20px; width:100px; text-align:center;" |3.91
+| style="height:20px; width:100px; text-align:center;" |3.88
+| style="height:20px; width:100px; text-align:center;" |3.88
+| style="height:20px; width:100px; text-align:center;" |3.89
+| style="height:20px; width:100px; text-align:center;" |0.03
+|-
+| style="height:20px; width:100px; text-align:center;" |Method 3
+| style="height:20px; width:100px; text-align:center;" |3.57
+| style="height:20px; width:100px; text-align:center;" |2.89
+| style="height:20px; width:100px; text-align:center;" |2.93
+| style="height:20px; width:100px; text-align:center;" |3.13
+| style="height:20px; width:100px; text-align:center;" |0.68
+|-
+| style="height:20px; width:100px; text-align:left;" colspan = "6"|
 : The number [[pi]] is 3.14159265359 correct to 12 [[Significant Figures|significant figures]].
-: 3.1 is an [[accurate]] value for [[pi]] but it is not very [[precise]] - Close to the real number, but not many [[Significant Figures|significant figures]].
+Method 1: The most [[accurate]] [[measurement]]s because they are the closest to [[pi]] but they are not very [[precise]] because they have a [[range]] of 0.26.
-: 3.2111 is a [[precise]] value for [[pi]] but it is '''inaccurate''' - Not close enough to the real number, but has several [[Significant Figures|significant figures]].
+Method 2: These are the least [[accurate]] [[measurement]]s 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 [[Mean Average|average]] is the most [[accurate]] as it is the closes to [[pi]].
+|}