Docstoc

Introducing sampling - JenniferIngram

Document Sample
Introducing sampling - JenniferIngram Powered By Docstoc
					Lesson 3

INTRODUCING SAMPLING
Focus

   Identifying and clarifying the population
   Sampling variation
   What is a sample?
   Why sample?
Karekare College
PROBLEM

 Do boys at Karekare College tend to have
  longer popliteal lengths than girls at Karekare
  college?
DATA

 How will you collect the data?

   Make a graph?
   Take a sample…
Sample

 Why is a sample better than using the whole
  population?
   Practicable
   Takes less time


 How might we sample?
Sample  Population

 Can a sample tell us about the population?
   Sample is good enough to look at the population
   We can get general/overall ideas, not specifics


 We take a sample because it tells us about
  the population

 What do you think your graphs will look like?
In pairs – go sample…

 Take a sample of 30 girls and a sample of 30
  boys from your population
 Graph your data on the graphs provided
 Write at least three I notice statements about
  your sample
Share…

 Leave your graph and I notice statements on
  your desk…
 Go and look at other graphs.
 For each other graph observe (and write)
   One thing that is similar to your graph and
   One thing that is different from your graph
Conclusion

 Did the graphs of different samples give the
  same information?
 In what ways were they the same?
 In what ways were they different?
I notice…

 Statements from my data
I wonder…

 Inferential statements about what is
  happening back in the population

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:0
posted:4/8/2014
language:Unknown
pages:12