PLB 360 Homework #4 Due Friday, May 1, 2009 in class
Name________________________________
All problems must be done independently and by hand. You may check your
answers using SAS.
1. (35 pts) A plant ecologist designed a field experiment to test the effects
of nitrogen availability and light on species richness in a prairie community.
This is a 2 way-ANOVA with two factors: nitrogen and light. Nitrogen has
3 levels and light has two levels. Perform a 2-way ANOVA. Write out the H0
and HA. Present your work in an ANOVA table. Also, state the critical F and
the conclusions of your test. Use = 0.05.
Low High 11
Low Low 12
Low High 10
Low Low 3
Medium High 14
Medium Low 3
Medium High 15
Medium Low 5
High High 18
High Low 15
High High 20
High Low 12
