IDS 270 PRACTICE EXAM 2025/ 2026
QUESTIONS WITH VERIFIED
ANSWERS
The sampling distribution of a statistic is ... - correct answer -distribution of a set of
sample averages. the distribution of values taken by a statistic in all possible samples of
the same size from the same population
INDEPENDENT - correct answer -If one event has no affect on the other event, then the
two events are
DISJOINT - correct answer -If two events are _______ then they cannot both happen
simultaneously. Opposite of independent
example of disjoint - correct answer -Suppose we roll the Red die (and ONLY the Red die)
Let A be the event that the number of spots showing on the red die is three or less
Let B be the event that the number of spots showing on the red die is four or more
So if A happens then B cannot happen
And if B happens then A cannot happen
random variable - correct answer -is a variable whose value is a numerical outcome of a
random phenomenon. ex: how many times you get heads when you toss a coin four times
, probability distribution - correct answer -of a continuous random variable x is described as
a density curve. the probability of any event is the area under the density curve and above
the values of x that make up the event
A rust prevention treatment is applied to a new car. The response variable is the length of
time before rust begins to develop on the vehicle. - correct answer -{The amount of time
before rust appears}
Choose and American household at random at let X be the number of persons living in the
household. - correct answer -discrete
a telephone survey research company is not able to get a woman to answer questions
about local traffic conditions because she is busy baking cookies - correct answer -
nonresponse bias
a student polls his friends to get data regarding grades at his university and represents his
findings as being representative of all students at that university - correct answer -
convient sample
a certain IDS 270 instructor does not answer questions about his drinking habits while an
undergraduate at the University of Michigan with complete accuracy - correct answer -
response bias
QUESTIONS WITH VERIFIED
ANSWERS
The sampling distribution of a statistic is ... - correct answer -distribution of a set of
sample averages. the distribution of values taken by a statistic in all possible samples of
the same size from the same population
INDEPENDENT - correct answer -If one event has no affect on the other event, then the
two events are
DISJOINT - correct answer -If two events are _______ then they cannot both happen
simultaneously. Opposite of independent
example of disjoint - correct answer -Suppose we roll the Red die (and ONLY the Red die)
Let A be the event that the number of spots showing on the red die is three or less
Let B be the event that the number of spots showing on the red die is four or more
So if A happens then B cannot happen
And if B happens then A cannot happen
random variable - correct answer -is a variable whose value is a numerical outcome of a
random phenomenon. ex: how many times you get heads when you toss a coin four times
, probability distribution - correct answer -of a continuous random variable x is described as
a density curve. the probability of any event is the area under the density curve and above
the values of x that make up the event
A rust prevention treatment is applied to a new car. The response variable is the length of
time before rust begins to develop on the vehicle. - correct answer -{The amount of time
before rust appears}
Choose and American household at random at let X be the number of persons living in the
household. - correct answer -discrete
a telephone survey research company is not able to get a woman to answer questions
about local traffic conditions because she is busy baking cookies - correct answer -
nonresponse bias
a student polls his friends to get data regarding grades at his university and represents his
findings as being representative of all students at that university - correct answer -
convient sample
a certain IDS 270 instructor does not answer questions about his drinking habits while an
undergraduate at the University of Michigan with complete accuracy - correct answer -
response bias
