Paul and Howard made a conjecture that the average size of TV screens has increased
rapidly in the last decade-they both remember the relatively small TVs they had
when they were in elementary school. They collected data about the size of TVs each
year for several years (www.flowingdata.com).
e.
f.
h.
2002 2003 2004 2005 2006 2007 2008 2009
Year
46 42 42
Average size of TV (in) 34
34
46
46
46
a.
b.
C.
d.
Make a scatterplot of size over time. Enter the year 2002 as year "2."
What is the equation of the LSRL? Sketch it.
Use a residual plot to analyze whether a linear plot is appropriate.
Describe the association between average size of TVs and time. Your
description should include an interpretation of the slope.
Predict the average size of a TV screen in 2015. How confident are you that
your prediction will be correct?
Interpret the y-intercept in context. Does it make sense?
The largest residual is 6.57. What does this mean in context?
What are the equations of the upper and lower bounds? Graph them on your
scatterplot with dashed lines.