12.07.2015 Views

“Mathematical Knowledge for Teaching” VOLUME 2 - AMESA

“Mathematical Knowledge for Teaching” VOLUME 2 - AMESA

“Mathematical Knowledge for Teaching” VOLUME 2 - AMESA

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

THE BIASED INTERPRETATION OF DATA USING MEASURESOF CENTRAL TENDENCYMamoshibudi MabaleCapricorn District: LimpopoThe presentation is one that I have used when I workshop FET Mathematics andMathematics Literacy educators on the concepts of measures of central tendency. Thepresentation does not focus so much on how to calculate the measures of centraltendency but on how people interpret a calculated measure of central tendency. Italso addresses bias when presenting or interpreting data by using Circuit results.ASSESSMENT STANDARDSThe following Assessment Standards <strong>for</strong> Grades 10 – 12 mathematics andmathematical literacy are covered by this presentation:MATHEMATICS:10.4.1 (a): Collect, organise and interpret univariate numerical data in order todetermine measures of central tendency (mean, median and mode) of grouped andungrouped data and know which is the most appropriate under given conditions.10.4.3 (a), 11.4.3 (a) and 12.4.3 (a): Identify potential sources of bias, errors inmeasurement, and potential uses and misuses of statistics and chars and their effects.10.4.3 (b), 11.4.3 (b) and 12.4.3 (b): Effectively communicate conclusions andpredictions that can be made from the analysis of dataMATHEMATICAL LITERACY:10.4.3; 11.4.3; 12.4.3: Understand that data can be summarised and compared indifferent ways by calculating and using measures of central tendency <strong>for</strong> more thanone set of data, inclusive of mean, median and mode10.4.4; 11.4.4; and 12.4.4: Critically interpret data in order to draw conclusions onproblems investigated to predict trends and to critique other interpretationsINTRODUCTIONWhile the purpose of the first part of the workshop was to help teachers to calculatemeasures of central tendencies, the rest of the workshop was used to help teachers tointerpret the calculated values.Exam results were presented to the teachers. What was important was that theyshould use the same data to calculate the median, mean and mode so that they couldsee how the same data can be interpreted differently. I also wanted to show them howtheir interpretations of the results and their conclusions could lead to misconceptionsdepending on which measure of central tendency was used.23

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!