The Vuvuzela captured international attention during the 2010
World Cup in South Africa. In its modern incarnation, the vuvuzela
is a plastic horn, about 65cm long, that can produce a sound loud
enough to cause permanent hearing damage. Blowing a vuvuzela
requires a fair amount of air pressure, and Lai et al. (2011) were
concerned that vuvuzela use by anyone carrying a pathogen would
cause airborne contagions to be spread broadly through a crowd.
They tested this idea with an experiment that compared the
concentration of aerosol droplets or particles produced by people
blowing vuvulzelas to that produced by the same people shouting
instead. The data, measured as thousands of particles per liter,
for 8 individuals are given in the table below.
Particle Concentration (1000s/liter)
Person Vuvuzela
Shouting
| 1 | 606 | 6.1 |
| 2 | 1077 | 6.4 |
| 3 | 220 | 1.3 |
| 4 | 396 | 1.8 |
| 5 | 1197 | 6 |
| 6 | 178 | 1.5 |
| 7 | 645 | 2.9 |
| 8 | 944 | 2.9 |
Take the log transformation of each value and then calculate the
standard deviation of the mean difference (round your answer to
four decimal places).
