Statistics- Hypothesis Testing on Facebook.

1. Koichi Tachiya
Average viewing time

3. Upper Tail Test
μ0 : μ ≤ 13.3333
μa : μ > 13.3333
(13.3333min/day)

4. Median=15
Mode=10
Max=40
Minimum=2
Range=38
n=64
x̄=16
Variance
S2=Σ(xi-x̄)2=87.6875
64-1
Standard Deviation
S=√S2=9.3641

5. n=64
x̄ =16
μ0 =13.3333
σ =9.3641604
α=.05
“σ Known case Upper tail test”
Z= x ̄- μ0
σ/√n
Z= 16-13.3333 = 2.6667 = 2.2782
9.3641/√64 1.1705

6. μ0 : μ ≤ 13.3333
μa : μ > 13.3333
P-value ≤ α α = .05
.0113 ≤ .05
“Reject μ0”
Z= 2.2782
Area = .9887
P-value = 1-.9887
= .0113

7. Interpolations/Recommendation
• The number of the time that people
spend on FB is still increasing.(60% of
the time spent on Facebook is from
mobile devices.)
• Nielsen might not add the data.
• We are wasting time on Facebook
for 8h/month.
(=16minutes/day or =96h/year)

8. References
(2012). top 10 web brands for march 2012 (u.s., total).
Nielsen. Retrieved from
http://blog.nielsen.com/nielsenwire/online_mobile/march-
2012-top-us-online-brands/
(2012). Top 10 web brands for september 2012(u.s., total).
Nielsen. Retrieved from
http://blog.nielsen.com/nielsenwire/online_mobile/septem
ber-2012-top-us-web-brands/