Midterm/ 115 Qs with Certified Solutions.
Determine whether the sampling method described below appears to be sound or is flawed.
In a survey of 538 subjects, the following question was posted on a newspaper's website: "In
your view, are nuclear plants safe?" The survey subjects were Internet users who chose to
respond to the question posted on the electronic edition of the newspaper. - Answer: - It is
flawed because it is a voluntary response sample.
Which of the following is NOT a voluntary response sample? - Answer: - Quiz scores from a
college level statistics course are analyzed to determine student progress.
Determine whether the underlined number is a statistic or a parameter.
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,In a study of all 2669 students at a college, it is found that 25% own a computer - Answer: -
Parameter because the value is a numerical measurement describing a characteristic of a
population
State whether the data described below are discrete or continuous, and explain why.
The heights of trees in a forest - Answer: - The data are continuous because the data can take
on any value in an interval
Assume that hybridization experiments are conducted with peas having the property that for
offspring, there is a 0.75 probability that a pea has green pods. Assume that the offspring peas
are randomly selected in groups of 30. Complete parts (a) through (c) below. - Answer: a. Find
the mean and the standard deviation for the numbers of peas with green pods in - the groups of
30.
The value of the mean is μ=22.522.5 peas.
(Type an integer or a decimal. Do not round.)
- The value of the standard deviation is σ=2.42.4 peas.
(Round to one decimal place as needed.)
b. Use the range rule of thumb to find the values separating results that are significantly low or
significantly high.
Values of 17.817.8 peas or fewer are significantly low.
(Round to one decimal place as needed.)
Part 4
Values of 27.227.2 peas or greater are significantly high.
(Round to one decimal place as needed.)
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, c. Is a result of 15 peas with green pods a result that is significantly low? Why or why not? The
result is significantly low, because 15 peas with green pods is less than 17.817.8 peas. (Round to
one decimal place as needed.)
Determine whether the sampling method described below appears to be sound or is flawed.
In a survey of 580 subjects, the following question was posted on a newspaper's website: "In
your view, are nuclear plants safe?" The survey subjects were Internet users who chose to
respond to the question posted on the electronic edition of the newspaper. - Answer: - It is
flawed because it is a voluntary response sample.
Determine which of the four levels of measurement (nominal, ordinal, interval, ratio) is most
appropriate.
- States in a region - Answer: - nominal
Determine whether the given value is from a discrete or continuous data set.
When a car is randomly selected, it is found to have a weight of 1886.3 kg. - Answer: - A
continuous data set because there are infinitely many possible values and those values cannot
be counted
Determine whether the description corresponds to an observational study or an experiment.
-Research is conducted to determine if there is a relation between kidney function in
adults and childhood-onset diabetes - Answer: - Observational study
Identify the type of sampling used (random, systematic, convenience, stratified, or cluster
sampling) in the situation described below.
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