Scale on my graphs

I see that when I was making those graphs during the past few posts, I was inconsistent on where the bottom of the graph was. In other words, sometimes I started at zero, and sometimes I didn’t. I am beginning to think I should have been more consistent and had them all start at zero.

What say you?


Published in: on August 23, 2010 at 2:29 am  Comments (3)  

The URI to TrackBack this entry is:

RSS feed for comments on this post.

3 CommentsLeave a comment

  1. Consistency is good!


  2. There’s no reason to force yourself to a same baseline regardless of what you are showing. If you’re comparing two things on two charts, then having the same scale is good, because otherwise you may exaggerate the differences.

    But generally, if you just said “I should always start at zero,” and the trend you were showing was very small, you’d have a chart with a lot of white space and the data you’re trying to show would be lost.

    The desire to be consistent shouldn’t outweigh the point of the chart in the first place. Nor should a minute change be exaggerated through too much detail on inconsequential data. I think handling it case by case is appropriate, and what how you interpret the data is more important than the scale of the chart itself.


  3. I was trying to make it so that some sort of a trend could, in fact, be seen. However, the changes over the past 7 years or so in pass rates have generally been rather small, except for when DCPS switched from the SAT-9 to the DC-CAS. I am worried that changing scales has made my analyses seem like the growths and drops are larger than they really were.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: