Lighting A manufacturer of leather products would like to imbue its retail stores with a warm ambiance. It tested two types of lighting with random samples of younger (20 to 30 years old) and older...

Lighting A manufacturer of leather products would like to imbue its retail stores with a warm ambiance. It tested two types of lighting with random samples of younger (20 to 30 years old) and older (more than 65 years old) customers. Customers were shown a mock-up of a retail store and asked to rate the warmth of the showroom on a scale of 1 to 8.²

(a) Are there any possible lurking variables in this analysis? Explain.

(b) Examine the profile plot of a two-way ANOVA of the rating by the two factors, age and lighting. What does this plot suggest has been shown by the experiment?

(c) Are the conditions met for using the model of a two-way ANOVA? Why or why not?

(d) What conclusions can you make from the twoway Anova?