1. Blake Colyer & Max Breidenstein

2.  College students are deprived of sleep and heavy caffeine users (coffee, tea, energy drinks) which affects alertness  Attention and alertness are linked, so…

3.  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 http://www.speederandearls.com/

4.  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

5.  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 )

6.  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 http://www.tobii.com/en/about-tobii/what-is-eye-tracking/

7.  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

8.  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 51.58360.76 61.73450.823 71.87540.925 82630.95

9.  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