Re: [Gretl-users] Gretl-users Digest, Vol 50, Issue 31

Send Gretl-users mailing list submissions to gretl-users(a)lists.wfu.edu To subscribe or unsubscribe via the World Wide Web, visit http://lists.wfu.edu/mailman/listinfo/gretl-users or, via email, send a message with subject or body 'help' to gretl-users-request(a)lists.wfu.edu You can reach the person managing the list at gretl-users-owner(a)lists.wfu.edu When replying, please edit your Subject line so it is more specific than "Re: Contents of Gretl-users digest..." Today's Topics: 1. Drawing lines on a scatter plot (Allin Cottrell) 2. Re: Drawing lines on a scatter plot (Allin Cottrell) ---------------------------------------------------------------------- Message: 1 Date: Wed, 23 Mar 2011 15:06:05 -0400 (EDT) From: Allin Cottrell&lt;cottrell(a)wfu.edu&gt; Subject: [Gretl-users] Drawing lines on a scatter plot To: Gretl users&lt;gretl-users(a)lists.wfu.edu&gt; Message-ID:<Pine.A41.4.58.1103231504480.393216@f1n11.sp2net.wfu.edu> Content-Type: TEXT/PLAIN; charset=US-ASCII I'm forwarding this (which got bounced by mistake). Allin Cottrell Date: Wed, 23 Mar 2011 13:32:43 -0400 From: Data Analytics Corp.&lt;walt(a)dataanalyticscorp.com&gt; To: gretl-users(a)lists.wfu.edu Subject: Drawing lines on a scatter plot Hi, I created a simple scatter plot of the log of sales (l_Sales) on the vertical axis and the log of price (l_Price) on the horizontal. Now I want to draw a vertical line and a horizontal line, both at their respective means. I tried to edit the graph and add a line using the Lines tab. I enter a formula such as mean(l_Price). But I got an error: How can I add the lines? Any suggestions are appreciated. Thanks, Walt ________________________ Walter R. Paczkowski, Ph.D. Data Analytics Corp. 44 Hamilton Lane Plainsboro, NJ 08536 ________________________ (V) 609-936-8999 (F) 609-936-3733 walt(a)dataanalyticscorp.com www.dataanalyticscorp.com _____________________________________________________ ------------------------------ Message: 2 Date: Wed, 23 Mar 2011 15:27:51 -0400 (EDT) From: Allin Cottrell&lt;cottrell(a)wfu.edu&gt; Subject: Re: [Gretl-users] Drawing lines on a scatter plot To: Gretl list&lt;gretl-users(a)lists.wfu.edu&gt; Message-ID:<Pine.A41.4.58.1103231517040.393216@f1n11.sp2net.wfu.edu> Content-Type: TEXT/PLAIN; charset=US-ASCII On Wed, 23 Mar 2011, Walt wrote: > I created a simple scatter plot of the log of sales (l_Sales) on the > vertical axis and the log of price (l_Price) on the horizontal. Now I > want to draw a vertical line and a horizontal line, both at their > respective means. I tried to edit the graph and add a line using the > Lines tab. I enter a formula such as mean(l_Price). But I got an > error: How can I add the lines? Any suggestions are appreciated. Formulas entered via the GUI graph editor are fed directly to gnuplot, which doesn't know about "l_Price". However, (a) You can add the y-mean by looking up that variable's summary statistics in gretl and using the graph editor to add a line at that value. For example, if the y-mean is 3.65, just enter a "formula" of "3.65". (b) Adding the x-mean (a vertical line) is more awkward and you'll probably have to edit the gnuplot commands. (Save the graph "as an icon" then right-click the icon.) One way is to append a plot "line" using a single data-point, with x-value equal to the x-mean and y-value equal to the natural height of the graph. Here's an example, based on a scatter plot of price against sqft from gretl's data4-1: Before addition of vertical line: plot \ '-' using 1:($2) notitle w points, \ 52.35090729 + 0.1387503195*x title "Y = 52.4 + 0.139X" w lines, \ 317.49 title "mean(price)" w lines lt 3 1065 199.9 1254 228 [...] e After addition: plot \ '-' using 1:($2) notitle w points, \ 52.35090729 + 0.1387503195*x title "Y = 52.4 + 0.139X" w lines, \ 317.49 title "mean(price)" w lines lt 3, \ '-' using 1:2 title "mean(sqft)" w impulses lt 3 1065 199.9 1254 228 [...] e 1910.9 550 e In gnuplot "e" on a line by itself signals the end of an inline data block. Allin Cottrell ------------------------------ _______________________________________________ Gretl-users mailing list Gretl-users(a)lists.wfu.edu http://lists.wfu.edu/mailman/listinfo/gretl-users End of Gretl-users Digest, Vol 50, Issue 31 *******************************************