Data Nugget: Do insects prefer local or foreign foods? 2012 Data Worksheet native1 exotic2 invasive3 species species species prop leaf prop leaf prop leaf Native Squared Exotic Squared Invasive Squared Species herbivory herbivory herbivory Difference Difference Difference # damage damage damage (native; - x) (exotic; - x 2) (invasive; - X 3)2 1 0.042 0.000 0.000 2 0.016 0.000 0.000 3 0.074 0.010 0. 170 4 0.067 0.028 0.183 0.003 0.002 0.029 6 0.032 0.027 0.050 0.071 0.025 0.216 8 0.012 0.000 0.091 9 0.149 0.016 0.065 10 0.008 0.293 0.088 11 0.000 0.016 12 0. 167 0.006 13 0.000 0.000 14 0.004 0. 100 15 0.012 0.241 16 0.006 0.242 17 0.000 18 0.000 19 0.046 20 21 22 23 24 Sample 19 16 Size (n) 10 Mean * = X, = *3 = (x Sum of Squares (SS)= > (x; - x1) SS1 = SS2 = SS3 = Variance (s2) = (xi-x)2 (n - 1) $7 = S3 = What is your calculated t value when comparing native to invasive species?: What is the critical t value at p = 0.05? Is there a significant difference in average insect damage for the native vs invasive species? Explain