Good Graph! UNI Plant Physiology Spring 2005

Why make graphs? To summarize your data To contrast treatments To show what happens over time (conc., distance, etc.) To tell a story rather than give numbers Because you have to

Two main kinds Scatter plot (dots) Bar graph

Scatter graph: Start with the box

Independent axis: What?

X axis units

X axis tick labels

Dependent axis: What?

Y axis units

Y axis tick labels

Title: What’s it about?

Add the data at last

Connect the dots

Good Scatter Plot

Scatter or bar graph? Continuous variable (x) –Examples: temperature, size, weight –Scatter –Connect the lines Discontinuous variable (x) –Examples: pet type, number of feet, car model –Bar graph

Bar graph box

Bar graph independent axis

Bar graph dependent axis

Bar graph title

Bar graph data

The final product

FAQs Does it matter if I do a good job? –You make your story clear –You get extra points –You understand other’s graphs –You get your manuscript accepted How can I remember all of this? –You can’t (yet) –It’s all in the lab manual –With a checklist

The easy way Use a computer program Tell it exactly what you want –Graph type –Title –Axis labels (with units), ranges –Data and line types –Lots more possibilities