STA 409
ASSIGNMENT
NOTE: This assignment comprises FOUR (4) Sections.
SECTION A:
1.
Use appropriate procedural steps and statistical formula, along with a handheld or
mobile phone calculator, to compute or find the following ten (10) statistics from the
data values provided below, which were obtained from the population of values of a
continuous quantitative variable: mode, media, mean, standard deviation, range, semi-
inter-quartile-range, 2
nd
quartile, 7
th
decile, 2
nd
of 5-tiles.
2.4
4.3
5.2
4.8
6.1
5.3
4.9
3.3
1.8
2.7
6.4
5.2
3.3
NOTE: Section A must be done manually, showing all calculations, and with calculations
written out in the student’s own handwriting.
BACKGROUND INFORMATION FOR SECTIONS B, C, D:
Company X has just deployed a new information system to replace an old information system
in its Sales Department. The Research Department has been interested in assessing the
parameters of the experiences of the company’s customers in the old information system just
before it was replaced, as well as in the new information system after it was deployed, in
order to compare the new system with the old one and recommend appropriate actions. The
Research Department has decided to use quasi-experimental, survey research and random
sampling designs/methods to collect and analyze data on one of the variables, i.e.,
time (in
minutes) to serve
the following three types of customers in the old and new systems: Credit
customers, Cheque customers and Cash customers.
(a) Data collection with a system transaction log software one month before the old
system was retired.
(b) Data collection with the same system transaction log software one month, three
months and six months after the new system began operation.
SECTION B:
1.
You will receive by email a data set containing 1000 data values, which you should
assume is the total population of times taken to service different cash customer
transactions over time in the old system (CASHOLD). You should assume this
because in real life, the total population is not static and can never be known as the
population of cash transactions will increase continuously as new cash transactions
take place. Nevertheless, use this assumed population and the SPSS to find out:
(i)
Population mean, median, mode, range, quartiles, deciles, 27
th
, 43
rd
and 61
st
percentiles, quartile deviation, variance, standard deviation, for the population
of cash transaction times.
(ii)
Use random sampling procedures (simple random, or systematic random
sampling with different starting value each time) to take five different samples
of size 30 from the population, and calculate for each sample the sample
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