Public Services and Procurement Canada
Symbol of the Government of Canada

Institutional Links

 

Important notice

Writing Tips has been archived and won’t be updated before it is permanently deleted.

For the most up-to-date content, please consult Writing Tips Plus, which combines content from Writing Tips and The Canadian Style. And don’t forget to update your bookmarks!

Search Canada.ca
To begin your search, go to the alphabetical index below and click on the first letter of the word you are searching for.

logic: biased or suppressed data

These errors in logic both involve the misuse of data. A writer who resorts to biased data collects evidence from sources on only one side of the argument. A writer who suppresses data chooses data selectively, ignoring evidence that doesn’t support the conclusion he or she wants.

Example of biased data:

"More than 85% of people surveyed believe that the summer break for secondary school students is too short. Therefore, the academic year should be reduced to allow for a longer vacation."

[The people surveyed were all secondary school students. We can predict that most of them would prefer a longer vacation! Therefore, they represent only one side of the argument, and the sample is biased.]

Example of suppressed data:

"This new product has passed several tests. It meets safety standards and is ready to go on the market."

[The argument sounds good on the surface–but in this case, the writer has focused on positive test results only and has ignored a small number of tests showing evidence of risks. The writer has therefore suppressed important data.]

In building a logical argument, it is important to be sure that all the facts from both sides of the argument have been fairly presented.