14.8 Quick revision questions

A study (Alley et al. 2017) examined social media (SM) use, using a

… sample of Australian adults […] randomly selected from a database with Queensland landline telephone numbers. To be eligible, participants must be aged 18 or more and reside in Queensland.

Alley et al. (2017), p. 92

Part of the data are summarised in Table 14.10.

1. Compute the sample proportion of urban residents who use social media, \(\hat{p}_U\).
   416/984 = 0.423 568/984 = 0.577 416/568 = 0.732 568/416 = 1.365
2. Compute the sample proportion of rural residents who use social media, \(\hat{p}_R\).
   78/89 = 0.876 89/78 = 1.141 78/167 = 0.467 89/167 = 0.533
3. Compute the sample odds of urban residents who use social media.
   416/984 = 0.423 568/984 = 0.577 416/568 = 0.732 568/416 = 1.365
4. Compute the sample odds of rural residents who use social media.
   78/89 = 0.876 89/78 = 1.141 78/167 = 0.467 89/167 = 0.533
5. Compute the sample odds ratio of using social media, comparing urban to rural residents.
   1.365/1.141 = 1.196 1.1411/1.365 = 0.836

TABLE 14.10: The number of Queenslanders using and not using social media (SM) in rural and urban locations in a sample

	Doesn’t use SM	Uses SM	Total
Rural	78	89	167
Urban	416	568	984

References

Alley S, Wellens P, Schoeppe S, Vries H de, Rebar AL, Short CE, et al. Impact of increasing social media use on sitting time and body mass index. Health Promotion Journal of Australia. 2017;28:91–5.

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Copyright © Peter K. Dunn, 2021