Difference between revisions of "Chart2/TrendLines"

From Apache OpenOffice Wiki
Jump to: navigation, search
(→‎Trend line equation and coefficients)
 
(2 intermediate revisions by 2 users not shown)
Line 1: Line 1:
−
 
 
== Add polynomial regression type ==
 
== Add polynomial regression type ==
 
[[Image:Chart2_TrendLines01.png]]
 
[[Image:Chart2_TrendLines01.png]]
Line 23: Line 22:
 
* Get the mean value not only for Y but also for X. A special symbol could mark the intersection point (the center of gravity).  
 
* Get the mean value not only for Y but also for X. A special symbol could mark the intersection point (the center of gravity).  
 
* covered in http://www.openoffice.org/issues/show_bug.cgi?id=64816
 
* covered in http://www.openoffice.org/issues/show_bug.cgi?id=64816
−
 
−
 
−
 
−
 
−
== Trend line equation and coefficients ==
 
−
[[Image:Chart2_TrendLines05.png]]
 
−
* It's not possible to automatically add the equation of the trend line and the coefficients.
 
−
* This point is one of the last that block several schools migrations.
 
−
* covered in http://www.openoffice.org/issues/show_bug.cgi?id=7998
 
−
 
−
It is possible to add the equation manually, though. The linear regression formula is Y=mX+b, where m=the slope, and b=the intercept. Let's say you're plotting a regression where the X-axis is in A2:A44, and the Y-axis is in B2:B44.  Plot your scattergraph and place the regression line as you normally would. Select a cell near the graph, and enter
 
−
="Y = " & ROUND(SLOPE(A2:A44;B2:B44);2) & "X + " & ROUND(INTERCEPT(A2:A44;B2:B44);2).
 
−
That gives you the regression line's equation. In the cell just below the previous formula, enter
 
−
="R-square ="&ROUND(INDEX(LINEST(A2:A44;B2:B44;1;1);3;1);2).
 
−
That will present the r-square value. Select both cells, and choose Edit->Copy.
 
−
 
−
Now, make sure the Drawing toolbar is visible (View->Toolbars->Drawing). Select the text box, and draw one. Choose Edit->Paste, and clean up the box so that it fits the text. Click outside the text box. Select the text box again, and move it onto the graph area where you want it to be displayed. (I usually put mine under the legend.) You can then dress up the chart, the text box, and the legend for presentation. When you're done editing, and have the box looking nice, then select the text box. Hold down the shift key and select the graph area. Right-click, and choose "Group."
 
−
 
−
You can now select the chart, and copy and paste it into Writer, Impress, or Draw documents as you wish.
 
  
 
== Error bar for X ==
 
== Error bar for X ==
 
* Error bar for X added to the existent Y one  
 
* Error bar for X added to the existent Y one  
 
* covered in http://www.openoffice.org/issues/show_bug.cgi?id=42946
 
* covered in http://www.openoffice.org/issues/show_bug.cgi?id=42946
−
 
+
[[Category:Chart2]]
−
== Data source for values or the error bar ==
+
−
* Obtain the value of the error bar from row or column in Calc
+
−
* covered in http://www.openoffice.org/issues/show_bug.cgi?id=366
+

Latest revision as of 09:23, 25 November 2009

Add polynomial regression type

Chart2 TrendLines01.png


Allow more than one regression line for one series

Chart2 TrendLines02.png


Extrapolating of trend lines

Chart2 TrendLines03.png

  • Trend lines should also allow extrapolating. If data ranges from 1 to 5 but that x axes range from -2 to 10, then the trend line should display from -2 to +10.
  • In Excel, the setting is called forward forecast and backward forecast.
  • covered in http://www.openoffice.org/issues/show_bug.cgi?id=5085


Mean value for X and center of gravity

Chart2 TrendLines04.png

Error bar for X

Retrieved from "https://wiki.openoffice.org/w/index.php?title=Chart2/TrendLines&oldid=149590"
Personal tools