Review Sheet for Test I, Fall 2016
Colorado State University, Pueblo
Math 156 — Introduction to Statistics
Definitions
Terms you should know -- be able to state clearly what they mean, recognize
them in examples, and create your own examples of them
- individuals, sample, and population
- parameter and statistic
- variables/measurements, being categorical/qualitative or
quantitative
- pie chart
- bar graph
- stem[-and-leaf] plot
- histogram
- symmetric, skew
- quantitative measures of center and spread:
- mean $\bar{x}$ and median (and mode)
- using mean and median to determine right or left skew
- quartiles $Q_1$ and $Q_3$
- variance $s^2$, standard deviation $s$, IQR,
and range
- sensitivity of the above to outliers
- the five number summary
- boxplots (=box-and-whisker plots)
- outliers, the 1.5 IQR rule
- the $z$-score of a data value
- the Empirical or 68-95-99.7 Rule
- probability: the idea, also sample space, outcomes,
events, fair coins and dice
- Venn diagrams
- operations on sets
- intersection ("and") — corresponding probability rule (really only for independent events)
- union ("or") — corresponding probability rule
- complement ("not") — corresponding probability rule
- mutually exclusive events
- conditional probability
- [in]dependent events
- random variables [RVs], being discrete or continuous
- [probability] distribution of a discrete RV
- mean/expectation/expected value of a discrete RV
- density function of a continuous RV
- the Normal distribution
- the standard Normal distribution
Things to know how to do
- given some data:
- make any of the graphs mentioned above, by hand or with help from
an electronic tool
- compute any of the quantitative statistical measures above, by hand
or with help from an electronic tool
- interpret/apply any of the above qualitative terms for the given data
- determine if there are any outliers and, if so, what they are
- know the strengths and weaknesses of the various graphical and
quantitative statistical measures above, and chose the appropriate one in
a particular situation
- determine probabilities for events described in words
- know when to use conditional probability
- know how to compute a probability from a continuous RV density function
- making a Venn diagram
- writing down the distribution of a discrete RV and computing its
expectation
- tell if two events are dependent or independent
- take some text describing a statistical situation and do an ASE-type
analysis: name individuals, sample, population, variables and their types,
statistical methods used, give a critique.
- do not confuse mean and median or independent and mutually exclusive
- use the Empirical rule and the table or an electronic tool to find
normal probabilities
- always, always, always, explaining your work clearly and completely,
mixing explanation with calculation, and justifying each step of your work
Format of the test
Problems will be of a level of difficulty and
wording similar to those on homework and quizzes. There will also be one
problem with some information to interpret as if for an ASE. The total
points for the test will be well more than 100, you can choose which 100
points you want to do out of the available problems. This means you should
definitely choose to do first the problems about which you are the most
confident, only coming back for the rest after finishing your first pass
through the entire test.
Don't forget your calculator or whatever electronic tool[s] you like and
notes or books to consult. While you can consult notes, you should
always do so simply to make certain you have the right formula or you are
checking all of the appropriate conditions — you should know the general
shape of all the formulæ, results, and definitions.
How to Study
It might be a good idea to put together all of your Big Ideas, review them, and
make sure you know all of the things they describe. Make sure you can make a
Venn diagram, the distribution of a discrete RV, and do probability
computations. Make sure you can make histograms and boxplots, find outliers,
and talk about skew. Make sure you can tell if events are mutually exclusive
or independent, or use the fact that one of those is true, if you are told it
is.
Go over your quizzes and HW problems and make sure you know how to do those
kinds of things, and that you could do them again and get perfect scores on them
now. If you want more problems, try doing other problems in the books which are
near and similar to the ones which were assigned. If you do odd problems, you
can check the answer is correct — but remember that the answer is not
the important part, it is the explanation which is important. Maybe practice
writing good solutions with complete explanations and justifications of
every step.
Look at your ASEs and make sure you know how you could change them so that you
would get a better score (if that is possible).