8.3 Test for one proportion
According to Statistica.com, 30% of individuals in Sweden wore contact lenses in 2020 (the highest percentage in Europe).
Suppose a group of 35 Swedish computer programmers at a large company includes 12 that wear contact lenses. Is there evidence in this sample that a greater proportion of Swedish programmers wear contact lenses at this company, compared to the general Swedish population? Conduct a test, then write a conclusion (including a CI).
What assumptions are needed for this test to be statistically valid, and externally valid?