An analyst processes one item every 30 minutes, so 16 items are completed in her
ID: 3352254 • Letter: A
Question
An analyst processes one item every 30 minutes, so 16 items are completed in her first day of work. Her manager checks her work by randomly selecting an hour of the day, then reviewing all the items she completed that hour. Does this sampling plan result in a random sample? Simple random sample? Does this sampling plan result in a random sample? A. Yes, because all possible groups of n items have an equal chance of being selected. B. No, because all possible groups of n items do not have an equal chance of being selected. ° C. Yes, because each item has an equal chance of being selected. O D. No, because each item does not have an equal chance of being selected Does this sampling plan result in a simple random sample? A. Yes, because each item has an equal chance of being selected. O B. No, because each item does not have an equal chance of being selected O C. Yes, because all possible groups of n items have an equal chance of being selected D. No, because all possible groups of n items do not have an equal chance of being selected Click to select your answer.Explanation / Answer
Analyst does takes 30 minutes to process one item and processes 16items.Hence he/she does 2 items in one hour and does work for 8 hours.
Her manager randomly selects 1 hour from the 8 hours and inspects both the process of that hour only.
Probability of selecting 1 hour = 1/8. This is same for selection for all the hours.
Hence,
This sampling plan results in a random sample, because
A)Yes, because all possible groups of 8 hours have an equal chance of being selected.
Does this sampling plan result in a simple random sample?
No, because when he inspects 2 items from 16 items, he inspects all the items of a particular hour he selects ie the probability of selecting 2 items from 16 items is not equal for all the items.
B)No, because each item does not have an equal chance of being selected.