Example:
Misleading Graphs and
Misinterpreting of Statistical Data
Objectives: (1) To identify sources of deception in misleading graphs (2) To recognise the dangers of misinterpreting statistical data
Learning Unit: Presentation of data
Key Stage: 3
Materials Required: Calculators
Prerequisite Knowledge: Basic knowledge on different statistical graphs Description of the Activity:
1. The teacher distributes the worksheet to students.
2. Students are grouped in pairs to do the problems in the worksheet so that they can discuss with each other as most of the questions are open-ended.
3. Sufficient time should be given to students to discuss the problems.
4. After students completed the worksheet, some representatives from the groups are invited to give the answers and explanations to the class.
5. The teacher makes comments when appropriate.
6. The teacher can help students consolidate their concepts by asking them to bring daily life examples of misleading graphs and misinterpreting statistical data to the class in the next lesson for discussion.
1
Data Handling
Worksheet
A survey is carried out by the student union of a secondary school on the popularity of five clubs: Social Service Society, Junior Police Call, Community Youth Club, Road Safety Patrol and Girl Guide. The results of the survey are posted on the notice broad of the student union by means of a bar chart. See Figure 1.
Figure 1
2
Printed by : Graph Paper Printer software Download : http://perso.easynet.fr/~philimar Please, register now : https://order.kagi.com/?3PJ Printed by : Graph Paper Printer software Download : http://perso.easynet.fr/~philimar Please, register now : https://order.kagi.com/?3PJ
Social Service Society
Junior Police Call
Community Youth Club
Girl Guide
Road Safety Patrol
Popularity of Five Service Clubs
25
20
15 Percentage
The number of students being interviewed is 1200.
1. Take a glance at the bar chart. What is your impression on the popularity of the clubs?
_________________________________________________________________
_________________________________________________________________
_________________________________________________________________
_________________________________________________________________
2. Give reasons to explain why you have such an impression in Question 1.
_________________________________________________________________
_________________________________________________________________
3. What is the difference between the percentage of popularity of the most popular club and that of the least popular club? Does the result change your view in Question 1?
_________________________________________________________________
_________________________________________________________________
4. Is a bar chart a suitable statistical graph for illustrating the percentage of popularity of the five service clubs? If not, which statistical graph is more appropriate?
_________________________________________________________________
_________________________________________________________________
3
Data Handling
Notes for Teachers:
1. The problems in this example are modified real-life examples found in newspapers and magazines.
2. As most questions are open-ended, the teachers should guide students to start the discussion if necessary.
3. The teacher should avoid giving students a “model answer”. Their answers should be accepted as long as these answers are reasonable and justified.
4. If possible, the teacher can use real-life examples found in the Internet, newspaper or magazines as a follow-up exercise for students to feel the impact of influence of the misleading graphs and misinterpreting statistical data.
5. Sufficient time for discussion is important. Students should give not only answers of “yes” or “no” but also the explanations.
4
