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'Meaningful Statistics' printed from http://nrich.maths.org/
This article is really an activity idea to try with children which
includes bits on probability, what data to collect, how to collect
it, how to display the data and how to interpret the data.
The setting: Monday morning in school. Your class is gathered
around you on the carpet. You pose the following question "What can
you say about the child who will be the first one into the
playground next Monday morning break time?". Then follows a
discussion in which you act as the chair as much as possible. The
discussion centres around what 'things' (attributes) could describe
the child in question. For example, age, gender, what class they're
in, colour of hair, eyes etc., height, shoe size, number of
siblings, etc.
Next there is a discussion about the collection of information
(data) so as to be able, after interpretation, to make a good
description of the child. Incorporated in this discussion is the
question "Does it matter what order we collect, display and
interpret the data from these different attributes?". The class
then decides upon the who, what and how.
I have found the richness of discussion amazing and the collection
of data to be so meaningful that it has been entered into
enthusiastically. So the children decide, for example, to look at
data connected with number of siblings; gender; hair colour; eye
colour etc. It is that, that has led me to repeat this activity in
different schools. Typical answers could be (because each attribute
is in the majority):
Child with 2 siblings
Girl
Blonde hair
Class 3 pupil
Blue eyes, etc
The collection of the data is of minor significance and has been
done in an efficient way so that a lot of time is not spent just
going around classes collecting data.
Sometimes there is an actual child who has all of these attributes
which leads to a discussion again as to how that will not always be
the case. The seeing of who is in fact there first on the
playground is fun but of little mathematical importance. So there
would never have been very much point to just seeing who is first
in the playground on the previous ten days and then make a
guess.
I once had all the work done with a class when a 10 year old girl
said "I know who'll be first in the playground on Monday, it'll be
me because I'm on duty to go into the playground and ring the play
time bell"!
Sometimes I've suggested that, because of different circumstances,
an alternative may be better: "What can you say about the first
vehicle to pass the school gates at 11 on a particular day?". As
well as data about types of car, colour, number of doors etc. there
is also information like driven by a lady, has a child in a carry
cot inside, a window open, a dirty car and so on. In this case
there are climatic and social circumstances that affect the
information available.
In conclusion, when we are working in this area of mathematics
let's see that:
1/ The youngsters understand what they're trying to find out.
2/ They discuss at length what data is needed to help in the
challenge.
3/ There's plently of discussion about efficient ways of collecting
the data.
4/ The displayed data can be interpreted satisfactorily.
5/ Some conclusions are arrived at.
6/ It has been enjoyable!