Answer Happy

Consider a study to determine the type of display a travel agent
should use for booking airline reservations. Two types of
display are under consideration – Type A and Type B.
Type B is more expensive. Market research has shown that travel
agencies are concerned with the time it takes to make
reservations.
Therefore the question is: Which one, if either, of the two
types of display, Type A or Type B, allows travel agents to
make reservations faster? In addition, travel agents consider
a difference, on average, between the types of display of less
than 20 seconds would be of no consequence, whereas a
difference, on average, of 20 seconds or more could result
in considerable cost savings.
Some possible outcomes of the study are:
Note: The hypotheses associated with the
quoted P‐values are:
H0: There is no difference between the
underlying mean time to make a reservation using display Type A and
the underlying mean time to make a reservation using display Type
B.
H1: There is a difference between the
underlying mean time to make a reservation using display Type A and
the underlying mean time to make a reservation using display Type
B.
a) What is the hypothesised value?
[ Select ] ["0.05", "Less than
0.05", "0", "(-20, 20)", "20"]
b) Select the correct options to complete the
sentence about Case 1:
The estimated difference in Case 1
(x̅A - x̅B = 16.58) is
[ Select ] ["-3.91", "16.18", "16.99", "4",
"15.58"] (2d.p.) standard errors
[ Select ] ["above",
"below"] the hypothesised value.
c) Which case(s) demonstrates, at the 5% level
of significance, that the difference between the observed means,
x̅A - x̅B, is
statistically different from the hypothesised
value? [ Select ]
["Cases 1, 3 and 5", "Cases 1, 2 and 3", "Cases 2, 3 and 5", "Cases
1, 2 and 5", "Cases 2, 3 and 4", "Cases 1 and 3", "Cases 3, 4 and
5", "Cases 1, 4 and 5", "Cases 4 and 5", "Cases 1, 3 and 4", "Cases
1 and 2", "Cases 3 and 5", "Cases 2 and 5", "Cases 3 and 4", "Cases
2 and 3", "Cases 2, 4 and 5", "Cases 2 and 4", "Cases 1 and 4",
"Cases 1, 2 and 4", "Cases 1 and 5"]
d) Which case(s) are we are able to claim that
the difference between the underlying mean times to make
reservations when using the two types of displays:
- has practical significance
[ Select ] ["Cases 1, 2 and 4",
"Cases 4 and 5", "Cases 1, 4 and 5", "Cases 3 and 4", "Cases 3 and
5", "Cases 1 and 3", "Cases 1 and 4", "Cases 2 and 5", "Cases 1, 3
and 5", "Cases 1 and 2", "Cases 2 and 4", "Cases 2, 3 and 4",
"Cases 2, 3 and 5", "Cases 2 and 3", "Cases 2, 4 and 5", "Cases 1,
2 and 5", "Cases 1 and 5", "Cases 3, 4 and 5", "Cases 1, 3 and 4",
"Cases 1, 2 and 3"]
- does not have practical
significance [ Select ]
["Cases 2 and 5", "Cases 4 and 5", "Cases 3 and 4", "Case
3", "Cases 2 and 3", "Cases 3 and 5", "Cases 2 and 4", "Case 2",
"Cases 1 and 4", "Cases 1 and 2", "Case 4", "Case 5", "Case 1",
"Cases 1 and 3", "Cases 1 and 5"]
e) Select one case in which we have learned
nothing useful about the underlying mean times to make reservations
when using the two types of displays [
Select ] ["Case 5", "Case 2", "Case 1", "Case
3", "Case 4"]
f) Suppose the actual outcome for the study
is:
Select the correct option to complete the sentences interpreting
this output:
In this case the difference between the mean times to make
reservations when using the two types of displays
[ Select ] ["is", "is
not"] statistically significant (at the 5% level).
We [ Select ]
["are", "are not"] able to claim that the
difference between the underlying means has practical
importance.
With 95% confidence the underlying mean time to make a
reservation using display B is estimated to be somewhere
between [ Select ]
["0.0002", "35.5", "30", "(30. 41)", "2.591",
"41"] and [ Select ]
["35.5", "(30. 41)", "2.591", "30", "0.0002",
"41"] seconds [ Select ]
["slower", "faster"] than
the underlying mean time to make a reservation using display A.
Based on these results I would [ Select
] ["not be able to recommend which display to
use", "recommend display B", "recommend display
A"] .