Discuss which random sampling techniques are adopted in the following studies. (a) A researcher wants to find out the prevalence of anemia in school students. He splits schools into rural, urban, and peri-urban as the prevalence may be quite distinct between these regions. The second step 1 is to take a simple random sample within each categorized area in proportion to the numbers enrolled in the schools in each area.
(b) There are 24 canopy trees in the sampling universe of interest, and you want to take 10 measurements from a subset of this group. You number each tree (1-24), put numbers in a hat, and pick ten at random. The tree corresponding to the number is now part of your sampling subset.
(c) From the Yellowpage book of the current year, you pick out 20 pet stores at random.
(d) A researcher wants to examine the growth patterns of a specific plant growing national wide in U. S.A. Out of 50 states, he selected 10 states at random. Within the selected states, he picks out 15 cities at random in each state. Then He collects the plants from the chosen cities.