Question

1d: understand the differences between stratified sampling, cluster sampling, systematic sampling, and convenience sampling.
is the following statement an accurate method to collect a stratified sample?
ceo luciana wants to know about employee satisfaction at her social media marketing company. instead of surveying all her employees, she decides to survey a sample of 411 employees. she divides the employees into groups based on their job title. then she chooses a random subset of employees from each job title, with each subset having a size proportional to the number of employees with that job title. then, she combines the subsets to form the sample.
yes, this is a stratified sample
no, this is not a stratified sample
is the following statement an accurate method to collect a cluster sample?
farmer nathan wants to advertise the weight of cows on his farm. instead of weighing all the cows, he decides to weigh a sample of 233 cows. he divides the cows into groups based on the pasture they are in. then he randomly selects 8 pastures and then weighs all the cows in those pastures.
yes, this is a cluster sample
no, this is not a cluster sample

Explanation:

For the first part, in stratified sampling, the population is divided into strata (here, job - title groups), and a random sample is taken from each stratum in proportion to its size in the population. Luciana divides employees by job title, takes proportional random subsets from each group, which is the correct way to do stratified sampling.
For the second part, in cluster sampling, the population is divided into clusters (here, pastures), and some clusters are randomly selected, and all elements within the selected clusters are included in the sample. Farmer Nathan divides cows by pastures, selects 8 pastures randomly and weighs all cows in those pastures, which is cluster sampling.

Answer:

1. Yes, this is a stratified sample
2. Yes, this is a cluster sample