STATISTICAL REASONING FINAL
EXAM
a subset of a population
sample
a census is
a sample that tries to include the entire population
A simple random sample is
a sample that gives every other sample of the same size the same chance of being
selected
Bias in a sampling method
any systematic error that tends to occur in the same direction every time you use the
sampling methods
in probability and statistics what is the definition of a random phenomenon
something that is unpredictable in the short run, but predictable in the long run
what is sampling distributions
a probability distribution listing all the possible outcomes and their probabilities
what does the law of large numbers say
if you repeat an experiment many times the mean of observed outcomes approaches
the expected value
what does statistically significant mean
an observed effect is large enough so that it is unlikely to happen by chance
a company database contains the following INFO about each employee: age, date
hired, sex, ethnic group, job category, yearly salary.which are categorical
variables
sex, ethnic group, job category
the five number summary
min, q1, med,q3,max
your school has 1000 students. you ask 80 of them, "have you had a cold in the
last 3 months?" fifty six percent "yes".this is an example of an
observational study
in this situation the word "no" could be described as
EXAM
a subset of a population
sample
a census is
a sample that tries to include the entire population
A simple random sample is
a sample that gives every other sample of the same size the same chance of being
selected
Bias in a sampling method
any systematic error that tends to occur in the same direction every time you use the
sampling methods
in probability and statistics what is the definition of a random phenomenon
something that is unpredictable in the short run, but predictable in the long run
what is sampling distributions
a probability distribution listing all the possible outcomes and their probabilities
what does the law of large numbers say
if you repeat an experiment many times the mean of observed outcomes approaches
the expected value
what does statistically significant mean
an observed effect is large enough so that it is unlikely to happen by chance
a company database contains the following INFO about each employee: age, date
hired, sex, ethnic group, job category, yearly salary.which are categorical
variables
sex, ethnic group, job category
the five number summary
min, q1, med,q3,max
your school has 1000 students. you ask 80 of them, "have you had a cold in the
last 3 months?" fifty six percent "yes".this is an example of an
observational study
in this situation the word "no" could be described as