Wikipedia:Reference desk/Archives/Mathematics/2013 March 13

= March 13 =

Is this an error in the article?
This article has the following statements:

''...The top 10% of wage earners now make 12 times more than the bottom 10%, up from a ratio of six in the 1990s. Moreover, wages are not smoothly spread out even through the middle of the distribution. The top 10% of earners make almost five times more than the median 10%, but this median 10% makes just 0.4 times more than the bottom 10%...''

The first statement tells us that The top 10% of wage earners now make 12 times more than the bottom 10% but the second one implies that The top 10% of wage earners now make 7 times more than the bottom 10%((5 times as much as the median 10% which makes 1.4 times as much as the bottom 10% -> 5 * 1.4 = 7).

Is this an error or did I miss something? Diwakark86 (talk) 18:10, 13 March 2013 (UTC)


 * Hmm, their numbers would fit perfectly if the median made 2.4x as much, and 1.4x more rather than 1.4x as much and 0.4x more. I've concluded for sure that there's no way it can be a rounding problem given the significant figures involved. i kan reed (talk) 18:54, 13 March 2013 (UTC)


 * Yea, that article looks like junk, to me. For one, it should say the median 10% makes 1.4 times more than the lowest 10%, not 0.4 times more.  That writer doesn't seem competent at math.  And the difference between the lowest 10% and median 10% should be far more than 1.4 times, too. StuRat (talk) 04:26, 14 March 2013 (UTC)


 * Here's some actual data (the first chart on page 15): . It says the lowest decile has 0.5% of the nation's wealth, the middle decile (which I obtained by averaging the 5th and 6th deciles) has 5% of the nation's wealth, and the top decile has 45.5% of the nation's wealth.  This works out to about 10 times from the bottom to middle, about 9.1 times from the middle to top, and about 91 times from the bottom to the top.  These numbers bear no relationship with those in the article.  To be that far off, I suspect he just made everything up. StuRat (talk) 04:38, 14 March 2013 (UTC)


 * Also note that the article claims "the ideal Gini coefficient of inequality is zero". They apparently didn't think that through, either, since that would mean everyone made exactly the same amount, eliminating all incentive to get an education, work hard, and advance.


 * I've posted 2 replies to that article, summarizing the above. StuRat (talk) 05:26, 14 March 2013 (UTC)

Do note that if a earns 100, then b earning 1.4 times, earns 140 while c earning 1.4 times more earns 240 (140 more). That little word more can make a big difference. -- SGBailey (talk) 10:18, 14 March 2013 (UTC)
 * Yes, and that could apply to "...almost five times more than the median 10%" as well. Actually, in ordinary usage, that statement is ambivalent.JoergenB (talk) 10:31, 14 March 2013 (UTC)