Re: y versus x, or x versus y? [was: Re: st: quantile-quantile plots]

[Nick Cox <njcoxstata@gmail.com>]

Martyn Sherriff forwarded this link

<http://english.stackexchange.com/questions/107800/is-x-plotted-against-y-or-is-y-plotted-against-x>

Nick
njcoxstata@gmail.com


On 16 April 2013 09:54, Nick Cox <njcoxstata@gmail.com> wrote:
> Very interesting example; thanks for thinking about my question.
>
> I studied economics when young. I can't recollect if I was puzzled
> then that demand curves (your example) and supply curves were plotted
> with price on the vertical axis. But it also seems fair to regard
> price as the outcome or response that is being explained here, namely
> that price arises out of the interaction of supply and demand, just as
> much as the other way around. So on that argument this kind of diagram
> is not an exception.
>
> No doubt all the real economists and econometricians will correct me
> if I am wrong.
>
> I must look in the book reviewed in http://ejpe.org/pdf/4-2-br-6.pdf
>
> That review in turn yields a reference to broaden the horizons of all
> inequality-measuring economists and social scientists:
>
> Derobert, Laurent, and Thieriot, Guillaume. 2003. The Lorenz curve as
> an archetype: a
> historico-epistemological study. The European Journal of the History of Economic
> Thought, 10 (4): 573-585.
>
> But in terms of my original question, the language usages
>
> plot y versus x
>
> plot x versus y
>
> -- and whatever logic lies behind them -- it strikes me now hat a
> simpler explanation is just the algebraic convention of naming x
> coordinate first, as in "its coordinates are (x, y)", so there is
> merely a clash of conventions here.
>
> Nick
> njcoxstata@gmail.com
>
>
> On 16 April 2013 04:07, Yu Chen, PhD <profyuchen@gmail.com> wrote:
>
>> In economics, sometimes the vertical axis is used to plot independent
>> variable, and the horizontal axis is used to plot the dependent
>> variable. For example, when price goes up, you may buy less food.
>> Price is plotted in vertical axis, and the quantity of food is plotted
>> in horizontal axis. The curve is downward sloping. That might be the
>> reason that you heard people saying plot x versus y.
>
> On Mon, Apr 15, 2013 at 5:21 AM, Nick Cox <njcoxstata@gmail.com> wrote:
>
>>> * A note on "versus" or "against". I was brought up -- probably in
>>> school physics, but it was last century, so I can't give precise
>>> recollections -- to say "plot y versus x" where y is, not
>>> surprisingly, whatever is plotted on the y or vertical axis. That
>>> seems to me to match mathematics and physics usages such as y is a
>>> function of x, or output is a function of time, where the dependent
>>> variable (outcome, response) is always mentioned first. But I've come
>>> across people saying "plot x versus y". If anyone has a logic for that
>>> usage, I'd be interested to hear it.
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/faqs/resources/statalist-faq/
*   http://www.ats.ucla.edu/stat/stata/