Consider the following statements to estimate the total marine fish landings of our country:
(A) . Even though the sampling design adopted for the purpose is ‘stratified multistage random sampling’ and stratification
being done over space and time, cluster sampling and double sampling are also involved for selecting first stage units.
(B) . A month is divided into 3 groups of 10 consecutive days. Suppose that the 4th date (day) was selected from the group of
first 10 days of a month. Then 6 consecutive days from the selected day will be 4, 5, 6, 7, 8, 9 and these days are grouped
into 3 clusters of 2 consecutive days, i.e., dates (4 and 5) will form one cluster, while (6 and 7) and (8 and 9) will form the
other two clusters. From the 2nd group of 10 days, 6 days are systematically selected with a sampling interval of 10 days
from the first date selected from the group of first ten days. Thus 6 days In the 2nd group will be 14, 15, 16, 17, 18 and 19
forming 3 clusters of dates (14 and 15), (16 and 17) and (18 and 19). From the 3rd group. 6 days are selected with the
sampling interval of 10 days from the first day selected in the 2nd group, ie., the dates will be 24, 25, 26, 27, 28 and 29
whose clusters are (24 and 25), (26 and 27), (28 and 29). Thus there are 9 clusters of two days each in a month
(C) . Each maritime state is divided into several zones on the basis of geographical consideration and fishing practices. Nine
landing centres are selected at random from each zone for recording fish landings. Then 9 clusters, formed by a certain
procedure involving systematic sampling also within a month, are allotted randomly to the 9 selected landing centres
(D) . On the first day of observation data are collected from 6 AM to 12 Noon and in the next day, 12 Noon to 6 PM. The data
on night landings are collected by enquiry covering the period from 6 PM of the first day to 6 AM of the next day. Thus a 24
hour period is covered for a landing centre. This forms the ‘landing centre day’ and is the first stage sampling unit.
Choose the correct statements from the options given below:
