Subject:   Library




Grade:     6th
1
1
            % 75 percent of teens age 12-17 use the
            internet.




    True

    False
2       People under 18 make up what percentage of the U.S. population?



    A     10%

    B     24.1%

    C     29%

    D     48%
3          9% of the U.S. population speaks English as their first language.




    True

    False
4   What percent of teens are either “indifferent,” “don't care,” or “care but
    don't take an active role” in being concerned about the effects of man
    on nature?




      A    12.2%

      B    50%

      C    68.5%

      D    95.3%
5           Male high school students in the U.S. have higher SAT scores on
            average than females.




    True

    False
Should you believe all statistics?




          Let's take a closer look . . .
CHECK FOR RECENT DATA
        % 75 percent of teens age 12-17 use the internet.




True

False




  1950                        2000                          2009
                       This statement was
                       true in the year 2000!




        What are other examples of data that would go
        out of date quickly?
USE GOOD COMPARISON DATA


7   People under 18 make up what percentage of the U.S. population?




    A   10%

    B   24.1%

    C   29%

    D   48%
The census is a sample of what
population?




              http://www.census.gov/
CHECK THE SAMPLE
8   9% of the U.S. population speaks English as their first language.




       Yes


       No




                                                                   9% of the world’s
                                                                   population speaks
                                                                   English!




         http://news.nationalgeographic.com/news/2004/02/0226_040226_language.html
MAKE SURE IT’S A RANDOM SAMPLE

9
        What percent of teens are either “indifferent,” “don't care,” or “care
        but don't take an active role” in being concerned about the effects
        of man on nature?


    A       12.2%

    B       50%

    C       68.5%

    D       95.3%




    If this is a survey of teens that use the computer often, is there a chance this sample
    would be less likely to play outside? Would this change their views on the
    environment?



                    http://www.stageoflife.com/TeensandNature.aspx
Another example of a biased sample . . .



   Percent of Kids in
  Different Schools in
      Champaign

                                                 Jefferson: 100%




                                           Sample: 30 students at Jefferson Middle
                                                          School



                        Is this a random sample?
Percent of Kids in
   Different Schools in
       Champaign
                                                Jefferson: 30%




                                  Edison: 30%

                                                   Franklin: 30%




                                         Sample: 300
                                         Random: Yes




What kinds of places could you go to get a random
sample of middle school students?
BE CRITICAL

10
             Male high school students in the U.S. have higher scores on
             average than females.



     True

     False




             http://www.britannica.com/blogs/2009/07/more-on-the-male-female-sat-math-test-gap/
In 2007 the SAT was taken by
798,030 females but only 690,500
males, a gap of more than
100,000 people. Assuming that
SAT takers represent the top
portion of the performance
distribution, this surplus of
females taking the SAT means
that the female group dips farther
down into the performance
distribution than does the male
group. It is therefore not surprising
that females, on average, score
somewhat lower than males. The
gender gap is likely in large part a
sampling artifact.
20% of white youth . . .              50% of girls . . .




      Who knows you best?


                           90% of youth test scores




60% of teens like rap music

Stats quiz-6th

  • 1.
    Subject: Library Grade: 6th
  • 2.
    1 1 % 75 percent of teens age 12-17 use the internet. True False
  • 3.
    2 People under 18 make up what percentage of the U.S. population? A 10% B 24.1% C 29% D 48%
  • 4.
    3 9% of the U.S. population speaks English as their first language. True False
  • 5.
    4 What percent of teens are either “indifferent,” “don't care,” or “care but don't take an active role” in being concerned about the effects of man on nature? A 12.2% B 50% C 68.5% D 95.3%
  • 6.
    5 Male high school students in the U.S. have higher SAT scores on average than females. True False
  • 7.
    Should you believeall statistics? Let's take a closer look . . .
  • 8.
    CHECK FOR RECENTDATA % 75 percent of teens age 12-17 use the internet. True False 1950 2000 2009 This statement was true in the year 2000! What are other examples of data that would go out of date quickly?
  • 9.
    USE GOOD COMPARISONDATA 7 People under 18 make up what percentage of the U.S. population? A 10% B 24.1% C 29% D 48%
  • 10.
    The census isa sample of what population? http://www.census.gov/
  • 11.
    CHECK THE SAMPLE 8 9% of the U.S. population speaks English as their first language. Yes No 9% of the world’s population speaks English! http://news.nationalgeographic.com/news/2004/02/0226_040226_language.html
  • 12.
    MAKE SURE IT’SA RANDOM SAMPLE 9 What percent of teens are either “indifferent,” “don't care,” or “care but don't take an active role” in being concerned about the effects of man on nature? A 12.2% B 50% C 68.5% D 95.3% If this is a survey of teens that use the computer often, is there a chance this sample would be less likely to play outside? Would this change their views on the environment? http://www.stageoflife.com/TeensandNature.aspx
  • 13.
    Another example ofa biased sample . . . Percent of Kids in Different Schools in Champaign Jefferson: 100% Sample: 30 students at Jefferson Middle School Is this a random sample?
  • 14.
    Percent of Kidsin Different Schools in Champaign Jefferson: 30% Edison: 30% Franklin: 30% Sample: 300 Random: Yes What kinds of places could you go to get a random sample of middle school students?
  • 15.
    BE CRITICAL 10 Male high school students in the U.S. have higher scores on average than females. True False http://www.britannica.com/blogs/2009/07/more-on-the-male-female-sat-math-test-gap/
  • 16.
    In 2007 theSAT was taken by 798,030 females but only 690,500 males, a gap of more than 100,000 people. Assuming that SAT takers represent the top portion of the performance distribution, this surplus of females taking the SAT means that the female group dips farther down into the performance distribution than does the male group. It is therefore not surprising that females, on average, score somewhat lower than males. The gender gap is likely in large part a sampling artifact.
  • 17.
    20% of whiteyouth . . . 50% of girls . . . Who knows you best? 90% of youth test scores 60% of teens like rap music