Question

Instructions: For each of the figures, complete the following in preparation for the quiz. What do the data show? Write a summary statement that communicates the "big idea" contained in the figure. Your summary statement should be written in such a way that if someone did not know the technical langugage in the figure, he/she could understand the "big idea." Identify essential evidence in the chart that substantiates the "big idea." What, if any, information is missing from the figure? What more would you want to know in order to understand and evaluate the data? (Think about the issues raised by Joel Best in Damned Lies and Statistics

Answer 1

Here' the answer to the question. Please let me know in case you've doubts.

1. Summary :

Looking at the bar-chart we clearly see that the concentration of total wealth gain from 1983 -2009
is concentrated on the top 5%. The next 35% had a comparitively less total wealth gain
of 26%, whereas the top 5% took ~82% between them. The contribution of the remaining 60%
of the people in fact decreased by 7.5%. Hence, the "big-idea" that can be summarized is that
the majority of total wealth gain comes from Top 5% only, the contribution of the bottom 60% in-fact had shrank.

2. Evidence:

The big idea is supported clearly by the data in the bar-chart.

The first 2 bars represent a 81% of the increase in wealth during 1983-2009, coming from only top 2 buckets which account for only 5% of people. The next 35%'s share is just a 26% ( next 3 bars in blue). The bottom 60%'s contribution to total wealth growth in fact shrank by a total of 7.5% ( see red bars)

3. Ideally we would also want to know and is missing in the chart:

The top 5% could be the rich guys and already had good amount of wealth. Hence, their contribution to
creation of wealth could also have been more as the base of their wealth was more. In absolute terms their contribution to the total wealth gain could have been more. But relative to their own existing wealth they may not have created so much wealth and hence this chart here maybe a "misrepresention" and may convey the
fact that rich became richer by a dispropotionate amount - which is actually a wrong conclusion.

Hence, to evaluate the data points, would have wanted data points on the existing wealth of all buckets as of 1983. That would have given us more clearer idea of weather they actually made wealth disproportionately.