Each day a commuter takes a bus to work,
the transportation system has a phone app that tells her what
time the bus will arrive. She feels the app is often wrong,
making her late or missing the bus all together. For 6 weeks,
the rider randomly picks four times a week to measure if the
bus was off from the estimated arrival time at her stop to
(n =24). Each measurement is Actual Arrival Time App
Estimated Time. If the bus was early, she recorded the number
as a negative time difference. If the bus was on time, she
recorded it as a positive time difference. From her sample, the
average time difference of arrival versus the app is 0.77 minutes.
For ease she assumes the population is normal and the standard
deviation is ? = 2 ???????. If the bus app is consistently accurate
than the overall average should be close to zero.
State: Is there evidence that the average time between actual
arrival time and the bus app time is more than 0 minutes?
(1 point) State the and alternative hypotheses to answer
the question of interest.
(2 points) Check conditions for inference. List the conditions
and state whether they are met.
c. (2 points) Calculate the test statistic. Show work.
d. (1 point) What is the p-value for the test? Is it one or two
e. (3 points) Calculate a 90% confidence interval for
_. Show work.  0.7720833
f. Write a four-part conclusion describing the results.
_ (1 point) Provide a statement in terms of the alternative
_ (1 point) State whether the result is statistically
significant. That is, whether, or not, to reject the .
_ (1 point) State whether the result is practically significant
_ (1 point) Give an interpretation of the point and interval
_ (1 point) Include context.