Transcript Talk back to statistics ppt

TALK BACK TO
STATISTICS
Achievement Standard 2.11
• Evaluate a statistically based report
with justification and insight
• Identify sampling and possible nonsampling errors in surveys including
polls
Statistical Literacy ?
• “ statistical literacy relates to two interrelated components,
primarily (a) people’s ability to interpret and critically evaluate
statistical information, data-related arguments, or stochastic
phenomena,…..and (b) their ability to discuss or
communicate their reactions to such statistical information. “
• ( Gal, 2002)
• "…understanding the basic language of statistics (e.g.,
knowing what statistical terms and symbols mean and being
able to read statistical graphs), and understanding some
fundamental ideas of statistics."
• ( Gaise Report, 2007)
Statistical Literacy
• “ …the ability to interpret and
evaluate critically statistical
information in a variety of contexts
and from a variety of media. It is also
the ability to communicate that
interpretation in a way that can
impact decision-making”
• ( Watson, 2006)
2.11 Overview
• Prior knowledge
• Student preparation for Unit
• Importance of Context
• Evaluation of Reports
• Different forms of assessment
delivery
• Challenges
CONTEXT
• Contextual knowledge is essential
• Select a context that is appropriate for
your students
• In practice assessments encourage
students to research topic before starting
evaluation of report
• Share knowledge discovered in brainstorm
session
• Potential for cross-curricular project
EVALUATION OF REPORTS
• Develop a set of worry questions to include sampling
problems, questionnaire design & delivery etc.
• Explore probability misconceptions . For example,
equiprobability bias, expression of probabilities
• Research different types of data display. Technology allows
students to be more innovative than the traditional bar chart,
histogram, pie chart etc.
• Get students to write their own reports of a data set complete
with headlines and charts.
Who do you believe?
• No evidence cell phones
cause cancer : US oncologist
- The Hindu BusinessLine
News
• Link found between cell
phone use and increase in
brain tumours - WHO
“Worry Questions”
• Examples
• Who is the data about? Who or what was studied?
• Where did the data come from? Who paid for the investigation or research?
How was it collected?
• Was a sample used? How was it sampled? Was the sample randomly selected
and is it representative?
• How reliable or accurate is the data? What measurements or questions were
asked? Have measurements or terms been defined?
• What is the shape of the distribution of the data? Have they used the correct
summary statistics for the type of distribution?
• Are there any outliers? What can you conclude from any outliers?
• If there is a graph drawn – has it been drawn appropriately?
• Are the claims made sensible and supported by the data? If a claim is made is it
justified by facts?
• Can you suggest any extra information or calculations that should have been
carried out in order to evaluate the issue in question?
• Are there any alternative explanations from causes not discussed that might
result in a different interpretation of the data?
Assessment
• COMMUNICATION !
• Powerpoint slideshow
• Written report
• Wiki page
• Poster
• Oral presentation – speech
• Innovative data display
Challenges
• Different methods of assessment delivery
• Authenticity of work
• Potential for cross-curricular study
• Availability of resources
Useful Websites
Evaluation of statistical reports
•
•
•
•
•
http://www.mercurynie.com.au/mathguys/mercury.htm
http://www.simerr.educ.utas.edu.au/numeracy/default.html
www.statschat.org.nz
www.offsettingbehaviour.blogspot.com
www.thestatsblog.wordpress
• Innovative Data Display
• www.coolinfographics.com
• www.infographicsshowcase.com
• http://www.smashingmagazine.com/2007/08/02/data-visualizationmodern-approaches/
Over to You !
• GROUP ACTIVITY
• TWO REPORTS with apparently opposing views. Is the
evidence convincing ?
• Report Back – Are you convinced by the headline. What
evidence was presented to convince you?
• Are you sceptical of the headline claims ? What evidence was
presented that you are unsure of ?
• CONCLUSION – Will the article affect the way you use a cellphone ?
Importance of Statistical
Literacy ?
HG WELLS “ Statistical thinking will one
day be as necessary for efficient
citizenship as the ability to read or
write.”
( end of 19th century)