Blake Colyer & Max Breidenstein
College students are deprived of sleep and heavy caffeine users (coffee, tea, energy drinks) which affects alertness Attention and alertness are linked, so…
To determine how sleep and caffeine effect attention levels in a college aged population Along the way we will examine the possibility of a significant interaction because when tired, caffeine is a go-to for many students
3 x 3 Factorial ◦ Factor: Hours of Sleep (Fixed) 6 hours, 8 hours, 10 hours ◦ Factor: Caffeine Consumption (Fixed) 0 mg, 95 mg, 190 mg 18 individuals randomly assigned to 9 treatment combinations ◦ Experiment replicated 4 times
Y ijk = µ + α i + β j + (αβ) ij + e ijk i=1,2,3 j=1,2,3 k=1,2 ◦ µ = grand mean of attention ◦ α i = fixed effect of hours of sleep Σ α i =0, ◦ β j = fixed effect of caffeine consumption Σ β i =0 ◦ (αβ) ij = fixed effect of interaction between sleep and caffeine Σ(αβ) ij =0 ◦ e ijk = experimental error e ijk ~ NIID(0, σ e 2 )
Materials/Facilities ◦ 18 homogeneous sleeping facilities Sound proof rooms with bed ◦ 18 Infrared gaze tracking units and computers Machine that measures infrared reflection from cornea The more time spent viewing the screen, the greater the attention to the task Wandering eyes mean a wandering mind
Methods ◦ Subjects arrive night before with staggered bedtimes for common awakening hour of 8:00AM ◦ Sleep, wake up, drink coffee 20 minutes later ◦ Read short article whilst machine tracks eye movement
Φ = √((rΣΣτ ij )/(abσ 2 )) H o :τ ij =0 H a :τ ij =1.5σ Φ = √((r4.5 σ 2 )/(3*3 σ 2 )) Φ = √ (r / 2) rΦDf2 = ab(r-1) Power
Power = 0.90, α=0.05 The ideal replication size per treatment combination to achieve the given power was 7. Considering we have 9 treatment combinations, that would imply needing 63 subjects in total. When being realistic about cost, it would make more sense to use 18 subjects and replicate the experiment 4 times