Does Your Opinion Count?

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P R O J E CT G U T S
U NI T 1 : O P I N I O N D Y NA M I C S
Does Your Opinion Count?
How to Take a Poll
Background
Have you ever taken a survey? How did you get chosen for the survey?
Was it random? Do you think that surveys and polls reflect the reality of
a larger population? What do you think is the purpose of a poll?
Polling is a very common technique used during election time to get an
idea about how the population of a state or the country as a whole
might vote. Polling is also used by advertising companies to find out the
popularity of certain products. The polling information is then used in
various ways through the news or advertisements. Could the results of
these polls have an influence on the rest of the population? How many
people are needed to sample in order to get the best results?
Objective:
In this activity, students will use different techniques to take many
different sample ‘polls’ of a population. They will then analyze the data
to see how accurate their sampling methods were. Students will learn
about sample size and errors or biases that are associated with polls.
Materials- Each group will need:
Large poster-sized grid sheets of paper with the edges folded up
Data sheet
5 different kinds of beans or different colored beads (one type
should have more than the others)
Procedure:
Part I1. The Instructor will introduce the idea of taking a poll by holding a
bag in their hand and pulling out a bean at a time. On a board or
a place where everyone can see, someone should record the
data.
2. Without letting the students see, the instructor randomly gets a
sampling and has the students record the data. After the 3rd
sample, have students guess which bean ‘opinion’ is most
common.
3. Keep going, and after the 5th, 8th , 10th, etc. have them re-guess.
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UNIT 1: OPINION DYNAMICS
Discussion:
At what point did their opinion change? What was the difference between
the samples, could the order the beans came up in alter students perception
of which was most popular?
Part II1. Divide the group up into smaller groups of 2-3 people
2. Place the large piece of paper in the center of the table or on the
floor. Fold up the edges so that the beans don’t move off the paper.
3. Shake the beans over the large paper. Once on the paper, they
should not be moved.
4. Look at the beans, write your prediction about which bean preference
is most common.
5. Sampling Technique #1 Cover eyes, pick out 10 with eyes covered.
6. Write the information on the Data Sheet. Think about any problems or
biases that might have come up.
7. Clear/ respread the beans each time and use the same sampling
technique between trials. Keep track of your data on the Data Sheet.
Run each sampling technique at least 3 times. See below for the other
techniques
8. At the end of the 4 different sampling techniques, count the beans to
find the actual ‘winner.’
Discussion:
Which of the 4 sampling techniques was the most and the least effective?
What kinds of problems did you notice in the sampling techniques? How
might these relate to real polling that is done for elections and advertising?
Sampling Technique #1- Cover eyes, pick out 10 with eyes covered
Sampling Technique #2- use 3”x3” square- 1 square- count and record data
Sampling Technique #3- use 3 3”x3” squares- count and record data
Sampling Technique #4- You develop a sampling technique that is different
than the ones above.
UNIT 1: OPINION DYNAMICS
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