Difference between revisions of "Sample Size"

Latest revision as of 18:32, 18 December 2019

Key Stage 4

Meaning

Sample size is the number of readings or measurements taken in an investigation.

About Sample Size

The results of an investigation may be unreliable if a small sample size is used.

A small sample size increases the effect of anomalous results on the conclusion of the investigation.

A large sample size allows averages to be taken to reduce the effect of random errors.

A large sample size makes it easier to spot anomalous results.

Examples

Reliable Investigation

Hypothesis - The taller a person, the larger their foot size.

Method - Measure the height and foot size of a number of people.

Sample Size - 5 people.

This is an unreliable investigation because there are not enough people to be certain of any conclusion. They may all have very large feet and be short.

Hypothesis - The taller a person, the larger their foot size.

Method - Measure the height and foot size of a number of people.

Sample Size - 5,000,000 people.

This is a reliable investigation because there are enough people to average out any anomalous results. For every short person with large feet there is likely to be a tall person with small feet.

References

@@ Line 6: / Line 6: @@
 : The [[results]] of an [[investigation]] may be [[Reliable|unreliable]] if a small '''sample size''' is used.
 : A small '''sample size''' increases the effect of [[anomaly|anomalous]] [[results]] on the [[conclusion]] of the [[investigation]].
-: A large '''sample size''' allows [[Mean Average|averages]] to be taken to reduce the [[effect]] of [[Random Error|random errors]].
+: A large '''sample size''' allows [[Mean Average|averages]] to be taken to reduce the effect of [[Random Error|random errors]].
 : A large '''sample size''' makes it easier to spot [[anomaly|anomalous]] [[results]].
@@ Line 19: / Line 19: @@
 :[[Method]] - [[Measure]] the [[height]] and foot size of a number of people.
 : '''Sample Size''' - 5,000,000 people.
-This is a [[reliable]] [[investigation]] because there are enough people to [[Mean Average|average]] out any [[anomaly|anomalous]] [[results]].
+This is a [[reliable]] [[investigation]] because there are enough people to [[Mean Average|average]] out any [[anomaly|anomalous]] [[results]]. For every short person with large feet there is likely to be a tall person with small feet.
+===References===
+====AQA====
+:[https://www.amazon.co.uk/gp/product/1782945962/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945962&linkCode=as2&tag=nrjc-21&linkId=476bb5c8d1dfb5c08ac81b6d4d1c98d8 ''Sample size, page 10, GCSE Chemistry, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/178294639X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294639X&linkCode=as2&tag=nrjc-21&linkId=51599bb45a2bfaf7c1b6a978b2ca2616 ''Sample size, page 10, GCSE Combined Science Trilogy; Chemistry, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/1782945954/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945954&linkCode=as2&tag=nrjc-21&linkId=100574c08fbbb64318256eb79ed61a76 ''Sample size, page 11, GCSE Biology, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/1782946381/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946381&linkCode=as2&tag=nrjc-21&linkId=5ec5fc3f6429e30c1d9ab9bca2bccf93 ''Sample size, page 11, GCSE Combined Science Trilogy; Biology, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/1782945563/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945563&linkCode=as2&tag=nrjc-21&linkId=9a1d023a374038e6072f33c4f3cf808b ''Sample size, page 4, GCSE Biology; The Revision Guide, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe10268 ''Sample size, page 5, GCSE Combined Science; The Revision Guide, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/1782946403/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946403&linkCode=as2&tag=nrjc-21&linkId=32a0abb60dff015b15b50e9b1d7b4644 ''Sample sizes, page 10, GCSE Combined Science Trilogy; Physics, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/1782945970/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945970&linkCode=as2&tag=nrjc-21&linkId=a120d24dcc7cc7a58192069a3aafc1d2 ''Sample sizes, page 11, GCSE Physics; The Complete 9-1 Course for AQA, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/0198359373/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359373&linkCode=as2&tag=nrjc-21&linkId=952a73bbb09d222ecc4b50d200679849 ''Sample sizes, pages 262-263, GCSE Biology; Third Edition, Oxford University Press, AQA '']
+====Edexcel====
+:[https://www.amazon.co.uk/gp/product/1782948120/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948120&linkCode=as2&tag=nrjc-21&linkId=dedef775c6a43dbb0a609441525adac0 ''Sample size, page 11, GCSE Biology, CGP, Edexcel '']
+:[https://www.amazon.co.uk/gp/product/1782945741/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945741&linkCode=as2&tag=nrjc-21&linkId=30da4f2178da182547b62a7329d13b57 ''Sample size, page 4, GCSE Combined Science; The Revision Guide, CGP, Edexcel '']
+:[https://www.amazon.co.uk/gp/product/1782946748/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782946748&linkCode=as2&tag=nrjc-21&linkId=a4f0348fc37d0ba1bb52d27f8679581f ''Sample size, page 5, GCSE Biology; The Revision Guide, CGP, Edexcel '']
+:[https://www.amazon.co.uk/gp/product/1782948163/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948163&linkCode=as2&tag=nrjc-21&linkId=0fdbfd5dd397d6e24a9dfb250f08587f ''Sample sizes, page 11, GCSE Physics, CGP, Edexcel '']
+:[https://www.amazon.co.uk/gp/product/1782945725/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945725&linkCode=as2&tag=nrjc-21&linkId=694be7494de75af3349537d34e13f7f0 ''Sample sizes, page 5, GCSE Chemistry; The Revision Guide, CGP, Edexcel '']
+:[https://www.amazon.co.uk/gp/product/1782948147/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948147&linkCode=as2&tag=nrjc-21&linkId=f63dcd8345f4e49c717b39a228a36c7c ''Sample sizes, pages 10, 11, GCSE Chemistry, CGP, Edexcel '']
+====OCR====
+:[https://www.amazon.co.uk/gp/product/1782945660/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945660&linkCode=as2&tag=nrjc-21&linkId=83aa4500ad7759e7f401a1c5ba5df758 ''Sample size, page 5, Gateway GCSE Biology; The Revision Guide, CGP, OCR '']
+:[https://www.amazon.co.uk/gp/product/1782945679/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945679&linkCode=as2&tag=nrjc-21&linkId=a2db42f7b4bdf10cafaafa3bb9120940 ''Sample sizes, page 5, Gateway GCSE Chemistry; The Revision Guide, CGP, OCR '']
+:[https://www.amazon.co.uk/gp/product/1782945695/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945695&linkCode=as2&tag=nrjc-21&linkId=ceafcc80bcad6b6754ee97a0c7ceea53 ''Sample sizes, page 5, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR '']