DTA 565 practice questions
Which statement is false? Explain.
If μ = 52 and σ = 15, then X = 81 would be an outlier.
Three randomly chosen Seattle students were asked how many round trips they made to Canada last year. Their replies were 3,4,5. The geometric mean is ____________.
3.915
The mean absolute deviation is __________.
the average of all absolute deviations
Statistics for a sample are denoted by _____.
x̄, s2
The mean of a sample and standard deviation of a population are denoted by _______.
x̄, σ
The quartiles of a distribution are most clearly revealed in which display?
box plot
The mode is the least appropriate for _____________.
continuous data
Twelve randomly chosen students were asked how many times they had missed class during a certain semester, with this result: 3, 2, 1, 2, 1, 5, 9, 1, 2, 3, 3, 10. The geometric mean is ___________.
2.604
Is the set of all the footballs in the world a sample or population?
Population
True or False: A sample set consists of randomly selected points from a population.
True
Which is not true of the Empirical Rule?
it applies to any distribution
Which of the following is true?
line charts are not used fro cross-sectional data
When a sample has an odd number of observations, the median is the ________________.
observation in the center of the data array
Estimating the mean from grouped data will tend to be most accurate when ___________.
observations are distributed uniformly within classes.
Which has more data points; a sample or a population?
population
There are ten sections of a math course at a university. One section is randomly chosen for a survey about calculator preferences. The group of students in this section is a _____.
sample
The symbol ∑ is used to denote __________.
sum of data
Absolute deviations are _____________
always positive
From its 32 regions, the FAA selects 6 regions, and then randomly audits 25 departing commercial flights in each region from compliance with legal fuel and weight requirements. This is an example of ________.
cluster sampling
