Answer:
Methods of obtaining a sample of 600 employees from the 4,700 workforce:
Part A: The type of sampling method proposed by the CEO is Convenience Sampling.
Part B: When there are equal number of participants in both campuses, stratification by campus would give a more precise approximation of the proportion of employees who are satisfied with the cleanliness of the breakrooms than stratification by gender. Another method to ensure that stratification by campus gives a more precise approximation of the proportion of employees who are satisfied with the cleanliness of the breakrooms than stratification by gender is to ensure that the sample is proportional to the proportion of each campus to the whole population or workforce.
Step-by-step explanation:
A Convenience Sampling technique is a non-probability (non-random) sampling method and the participants are selected based on availability (early attendees). The early attendees might be different from the late attendees in characteristics such as age, sex, etc. Therefore, sampling biases are present. All non-probability sampling methods are prone to volunteer bias.
Stratified sampling is more accurate and representative of the population. It reduces sampling bias. The difficulty arises in choosing the characteristic to stratify by.
Answer:
D) a chi square test for independence.
Step-by-step explanation:
Given that we suspect that automobile insurance premiums (in dollars) may be steadily decreasing with the driver's driving experience (in years), so we choose a random sample of drivers who have similar automobile insurance coverage and collect data about their ages and insurance premiums.
We are to check whether two variables insurance premiums and driving experience are associated.
Two categorical variables are compared for different ages and insurance premiums.
Hence a proper test would be
D) a chi square test for independence.
317 is the answer you are looking for.
Answer:
0.590
Step-by-step explanation:
Cumulative frequency = number of new cases during a particular period / number of individuals at risk = number of people down with salmonella / total number of people present =49 /83 = 0.590
