Question

We are interested in understanding the impact of ambient temperature on walker aggression. Researchers took three random samples of walkers, divided them into separate temperature- controlled locations for five days, then tested their levels of aggression (the higher the score, the more aggressive the walker). Below are their aggression scores. Fifty Degrees Seventy Degrees Ninety Degrees SOURCESS Fobt Between Within Total

Answer 1

Solution:

The following null and alternative hypotheses need to be tested:

Ho: μ₁ = μ₂ = μ₃

Ha: Not all means are equal

The above hypotheses will be tested using an F-ratio for a One-Way ANOVA

Using excel,

First enter data in excel,

Data -------> Data analysis-------> one way anova with single factor

Input range: select all data

Alpha: 0.05

Ok

Output is:

ANOVA Source of Variation SSdfMS Between Groups 21.809522 10.90476 4.461039 0.026698 3.554557 Within Groups P-value F crit 44 18 2.444444 Total 65.8095220

Since it is observed that F_obt=4.461>F_crit=3.555, it is then concluded that the null hypothesis is rejected.

Conclusion: It is concluded that the null hypothesis Ho is rejected. Therefore, there is enough evidence to claim that not all 3 population means are equal, at the α=0.05 significance level.

Done