Mirex concentration, weight, capture year, and species of Lake Ontario Coho and Chinook salmon.

Format

A data frame with 122 observations on the following 4 variables.

year

a numeric vector of capture years

weight

a numeric vector of salmon weights (kg)

mirex

a numeric vector of mirex concentration in the salmon tissue (mg/kg)

species

a factor with levels chinook and coho

Source

From (actual data) Makarewicz, J.C., E.Damaske, T.W. Lewis, and M. Merner. 2003. Trend analysis reveals a recent reduction in mirex concentrations in Coho (Oncorhynchus kisutch) and Chinook (O. tshawytscha) Salmon from Lake Ontario. Environmental Science and Technology, 37:1521-1527.

Details

The year variable should be converted to a factor as shown in the example.

Topic(s)

  • Linear models

  • Other

Examples

Mirex$year <- factor(Mirex$year) lm1 <- lm(mirex~weight*year*species,data=Mirex) anova(lm1)
#> Analysis of Variance Table #> #> Response: mirex #> Df Sum Sq Mean Sq F value Pr(>F) #> weight 1 0.22298 0.222980 60.0785 8.586e-12 *** #> year 5 0.50667 0.101333 27.3028 < 2.2e-16 *** #> species 1 0.00000 0.000001 0.0004 0.9840448 #> weight:year 5 0.09491 0.018982 5.1143 0.0003287 *** #> weight:species 1 0.00240 0.002397 0.6457 0.4235926 #> year:species 5 0.02338 0.004677 1.2601 0.2873654 #> weight:year:species 5 0.01650 0.003299 0.8890 0.4916170 #> Residuals 98 0.36372 0.003711 #> --- #> Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1