Dr. V – Study Guide – Ch 1-8, plus “About proportions”
Given a N (3.1 ft, 1.2), what is the name (and units) for 1.2? How would you interpret it?
population’s standard deviation is 1.2
(same units). That measure of variability is roughly the
average distance of the data (or scores) from the 3.1 mean.
A median is preferred (over a mean) when data is . . . . .
How do you determine whether an observation is an outlier?
. . . Using a box plot,
be able to
determine the “boundaries” with the 1.5xIRQ rule
What adjectives could apply to histograms? What adjectives could apply to time plots? Why are
– Understand the basic
meaning of the following: bar charts, histograms,
population, sample, parameter, statistic, estimate, observational study, experiment, explanatory
variable, response (or outcome), confounding variable, probability, conditional probability,
complement, mutually exclusive (or disjoint), independent, random variable, inference, bias
(response, non-response, selection).
Snoring vs Life of the Party (See p 244):
P(likes-to-party) = ?, P(snore
likes-to-party) = ?, P
likes-to-party) = ?, P(likes-to-party
snores) = ?. Are “snoring” and “likes-to-party”
independent? Are snoring and likes-to-party disjoint?
Ch 8 – Random Variables
About discrete distributions
Suppose x = # phone calls over lunch to a particular office (X = 0, 1, 2, 3, 4) so that
What’s the P(X=4)?
. . .
gives you P(X=4)
What’s the expected number of phone calls?
. . . When you see “expected” or E(X),
think MEAN (and means get decimals). Here, it’s E(X) =
xp(x) = 0x0.2 + 1x0.35 +
2x0.25 + etc.