Zooplankton Depredation

Diversity of zooplankton (zooplankton) prey in each of 5 replicate blocks (block) of three treatment levels (treatment). By default, block is not coded as a factor.

Usage

Zooplankton

Format

A data frame with 15 observations on the following 3 variables.

treatment

a factor with levels control, high, and low

zooplankton

a numeric vector

block

a numeric vector

Source

inferred from Svanbäck, R. and D.I. Bolnick. 2007. Intraspecific competition drives increased resource use diversity within a natural population. Proceedings of the Royal Society of London Series B, Biological Sciences 274: 839-844.

Examples

Zooplankton
#>    treatment zooplankton block
#> 1    control         4.1     1
#> 2        low         2.2     1
#> 3       high         1.3     1
#> 4    control         3.2     2
#> 5        low         2.4     2
#> 6       high         2.0     2
#> 7    control         3.0     3
#> 8        low         1.5     3
#> 9       high         1.0     3
#> 10   control         2.3     4
#> 11       low         1.3     4
#> 12      high         1.0     4
#> 13   control         2.5     5
#> 14       low         2.6     5
#> 15      high         1.6     5

Zooplankton$block <- factor(Zooplankton$block)
str(Zooplankton)
#> 'data.frame':	15 obs. of  3 variables:
#>  $ treatment  : Factor w/ 3 levels "control","high",..: 1 3 2 1 3 2 1 3 2 1 ...
#>  $ zooplankton: num  4.1 2.2 1.3 3.2 2.4 2 3 1.5 1 2.3 ...
#>  $ block      : Factor w/ 5 levels "1","2","3","4",..: 1 1 1 2 2 2 3 3 3 4 ...

aov.fit <- aov(zooplankton ~ block + treatment,
  data = Zooplankton)
summary(aov.fit)
#>             Df Sum Sq Mean Sq F value  Pr(>F)   
#> block        4  2.340   0.585   2.792 0.10103   
#> treatment    2  6.857   3.429  16.366 0.00149 **
#> Residuals    8  1.676   0.209                   
#> ---
#> Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1