Question

Samples of three different species of amphibian (frog, toad and salamander) were collected and dissected and the number of parasites found within each was counted and recorded. The researchers are interested in determining whether the distribution of parasites across species is different. The number of parasites within each sample was counted and recorded. Toads Frogs Salamanders 1 6 a 3 11 5 111 8 17 Z 17 3 11 5 17 16 8 14 4 17 10 The researchers made a qq plot of the data. Does the normality assumption hold? 12 10 PRE 2.5 2.5 21.5 0.5 0 0.5 1 1.5 2 Theoretical Quantiles Yes, the normality assumption holds No, the normality assumption does not hold >] Suomi, Thies 0/2

Answer 1

Yes normality holds

No the normality assumption does not hold

$H_0:\mu_1=\mu_2=\mu_3$

$H_a:\mu_i \neq \mu_j ~for~some~i\neq j$

average rank for toads=6.00

average rank for frogs=5.30

average rank for salamanders=6.44

test statistic=0.50

p-value>0.1

MINITAB RESULT:

One-way ANOVA: number of parasites versus amphibian

Source DF SS MS F P
amphibian 2 6.37 3.18 0.50 0.614
Error 26 166.32 6.40
Total 28 172.69