STAT 180 SU Sampling and Surveys Introducing Statistics Discussion

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ABOVE IS THE TABLE 1 of UNIT 4

Question 4(a) Comment on the representativeness of the sample with respect to occupation, assuming that the full staff list in Table 1 of Unit 4 is the population. [3 marks]

MY RANDOM 17 PEOPLE SELECTION

Question5 (Unit 4) – 8marks

A population of 505 customers were asked about their satisfaction with a company’s car parking facilities. Their responses are given in Table 3 below.

(a) What is the median response for this population? Showy our working. [ 2 marks ]

(b) Figures A, B and C below each show a distribution of the sample median, but they are based on sample medians for samples of different sizes from different populations.

• Sample 1 is the distribution of the sample median for samples of size3fromthe population given in Table 3.

• Sample 2 is the distribution of the sample median for samples of size17fromthe population given in Table 3.

• Sample 3 is the distribution of the sample median for samples of size 9 from a population different from that given in Table3 . Giving your reasons, say which figure relates to which sample. [4 marks]

(c) In reality, it is unlikely that all 505 customers would respond to the survey. What type of error would be introduced if many customers did not respond? Briefly describe an effect this could have on the results. [2 marks]