Colorado State University — Pueblo, Spring 2017
Math 156, Introduction to Statistics
Course Schedule and Homework Assignments
Here is a link back to the course syllabus/policy page.
This schedule is will be changing very frequently, please check it at
least every class day, and before starting work on any assignment (in case the
content of the assignment has changed).
Below, we refer to the class text Lies, Damned Lies, or Statistics
as LDLoS. The whole book is available here,
although below there will be links to particular sections of the book that
you are asked to read and in which you will find problems to do.
If you see the symbol
below, it means that class was videoed and you can get a link by e-mailing me.
Note that if you know ahead of time that you will miss a class, you should
tell me and I will be sure to video that day for you.
When there is a reading assignment, please read the named section(s) before
that day.
Homework for a particular day is due that day, either in class or
handed in at my office by 3pm.
Your e-mail address. (Please give me one that you actually check
fairly frequently, since I may use it to contact you during the
term.)
Your year/program/major at CSUP.
What you intend to do after CSUP, in so far as you have an idea.
Past math classes you've had.
The reason you are taking this course.
Your favorite mathematical subject.
Your favorite mathematical
result/theorem/technique/example/problem.
Anything else you think I should know (disabilities, employment
or other things that take a lot of time, etc.).
[Optional:] The name of a good book you have read
recently.
Please do this some time Monday. But as some direct incentive: I will
only enter your name into my gradebook and give you your Homework
Late Passes when I get this e-mail, so you really need to
do this assignment as soon as possible. [By the way, just to be fair,
in case you are interested, here is a
version of such a self-introductory e-mail with information as I would
fill it out for myself.]
Some content we discussed, terms defined:
some big picture discussion of what the whole subject of
statistics is about
individuals, population
variables, which can be categorical or
quantitative
Hand in BI1. This will be an unusual one: write down two or
three things you were surprised about in the organization of this
course. Be specific, mention types or numbers or formats of some
assignments, etc.
Here is an example of the kind of thing we
are looking for. (The "critique" in this example is very friendly and
positive — which is actually unsurprising, since the source is a
famously careful and impartial research organization — while
yours may not be as positive (e.g., sometimes it is fun to find
a published statistic which is full of errors!).
Hand in ASE1, if you did not already do so on Monday.
Going over HW1
Some content we discussed, terms defined:
electronic tools for basics statistical graphing and calculation
the median
outliers, informally
which measures of central tendency are sensitive to
outliers and which are not.
comparison between median and mean pointing towards the skew of
a histogram
Many web pages describe how to use your favorite calculator to do
statistical computations. If you have a TI-84, for example,
this
is a good reference for variance, standard deviation, and IQR. If you
have another calculator, just use your favorite search engine to look
for "compute standard deviation on a calculator name." You can
also find many smartphone apps, some probably free, on your favorite
app store. And finally, if you search for "online standard deviation
calculator," you will find many web pages which will do these kinds of
computations for you on whatever Internet-connected device you have.
Hand in BI4 on something from Monday's class or reading
variance and standard deviation, both for samples
and populations
This page (which we have seen before) explains how to compute IQRs on a
TI-84, if that's your calculator. If you have a different
calculator, just use your favorite search engine to look for
"compute IQR on a calculator name" or "compute quartiles on a
calculator name." You can also find many smartphone apps,
some probably free, on your favorite app store. And finally, if you
search for "online IQR calculator" or "online quartile calculator"
you will find many web pages which will do these kinds of
computations for you on whatever Internet-connected device you have.
a specifically data-driven organization, such as one of the
following [descriptions below, when in quotation marks and
italics are taken from the respective site's
self-description]
FiveThirtyEight
[FiveThirtyEight is an on-line journalism site which applies
careful research and thoughtful statistical modeling to
current stories in politics, economics, science, "life", and
sports. It was founded by Nate Silver, who has done
statistical analysis for sports betting and also predicted
state-by-state the outcomes in the presidential elections
of 2008 and 2012 with incredible accuracy.]
The Pew Research
Center ["Pew Research Center is a nonpartisan fact
tank that informs the public about the issues, attitudes and
trends shaping America and the world. It conducts public
opinion polling, demographic research, media content analysis
and other empirical social science research. Pew Research
does not take policy positions."]
The Gapminder
Foundation ["Gapminder is a non-profit venture –
a modern 'museum' on the Internet – promoting
sustainable global development and achievement of the United
Nations Millennium Development Goals."]
the Gallup polling
organization ["Gallup delivers forward-thinking
research, analytics, and advice to help leaders solve their
most pressing problems. Combining more than 75 years of
experience with its global reach, Gallup knows more about the
attitudes and behaviors of the world's constituents,
employees, and customers than any other organization."]
One thing you must avoid in ASEs is using as the source you
will analyze a website or textbook section which is statistical
instructional materials. The goals of ASEs is for you to work
with real, live data, not for you to take canned example from
a stat textbook or Wikipedia page on some statistical method or
terminology.
Hand in BI6 (on an idea from Friday's class or readings)
Today [Monday] is the last day to drop classes without a grade
being recorded.
independent and dependent variables [also called
explanatory and response variables]
deterministic and non-deterministic relationships
between variables
scatterplots; their shape, strength, and
direction
Hand in BI9 (on an idea from Friday's class or readings)
Hand in ASE3. See above, here and
here, for the required parts of an
ASE (the second of those explanations above also has a list of
a few sites you could go to in order to find materials for an
ASE, although of course something you are interested in yourself
would probably be much more fun). Please look for something which
mentions variability, standard deviation,
quartiles, and/or outliers, or which uses the
five-number summary or boxplots
Hand in BI13 (on an idea from Monday's class or readings)
Hand in HW5: problems 3.{1, 2, 3} on
this page of LDLoS.
:
Test I in class today. Make sure you are comfortable with
the material outlined on this review sheet.
Don't forget your calculator, or other favorite electronic
device, if you use one!
Yes, we do have class today, even though it is the federal
holiday commemorating the birthday of George Washington (who was
actually born on February 22nd, 1732), although
this holiday is often casually referred to as "Presidents' Day."
Test I post-mortem.
Hand in ASE4. Please try to find something which mentions
or uses scatterplots, correlation or the
correlation coefficient, or maybe even
[linear] regression
complement of a subset [event], notation $E^c$,
translation into English: not
probability rule for complements
Hand in BI14. This is a special one: please write a paragraph
about how you think Test I went for you. Are you perfectly content
with how it turned out? If not, what do you think was the cause of the
trouble? And what can you do next time to make things better?
intersection of sets [events], notation $A\cap B$,
translation into English: and
union of sets [events], notation $A\cup B$,
translation into English: or
disjoint events, notation $\emptyset$ for the
empty set
finishing the definition of a probability model
Venn diagrams — how to fill in numbers correctly
Hand in BI15 (on an idea from Wednesday's class or readings)
Hand in HW6: problems 4.{1, 2, 3} on
this page of LDLoS.
[NOTE: due to network problems, this assignment was not posted until
late Thursday afternoon. Therefore, if you hand it in on Monday, that
will not be considered late!]
the [probability] distribution of a [discrete]
random variable
the expectation of a [discrete] random variable
Hand in BI19 (on an idea from Friday's class or readings)
Hand in HW7, if you didn't hand it in on Friday
Hand in Quiz 5, which was handed out in class on Friday
— if you didn't pick up a copy in class, e-mail your instructor
and you will get a PDF by return email.
Hand in ASE5 on something from our unit on Probabily Theory.
Search in your favorite search engine for words like {\it probability,
likelihood, odds, risk, etc.} ... although such searches tend to turn
up mostly educational web pages (which are not allowed for ASEs, as
you surely remember). But if you add some other terms --
like odds of winning the lottery or probability of an
earthquake -- then you might find somethings.
Or else search just on one, reputable site (put "site:nytimes.com,"
for example, to restrict a search to that site) for more general words.
Here are the results of some such searches:
Feel free to use any of those, or else to find you own. If you have any
doubts as to whether it is a potentially good source for an ASE, email
your instructor with a link and you will get a quick response.
using electronic tools to compute Normal probabilities.
Hand in BI22 (on an idea from Friday's class or readings)
No ASE due today — in fact, none due this week. Although
there will be one due after Spring Break, so if you think you will be
unable to work at all over the break, it might make sense to start
that ASE now — maybe just going as far as finding a source and,
if you are worried about whether it will make a good ASE, asking your
instructor.
Hand in HW8: problems 4.{7, 8, 9, 10} starting on
this page of LDLoS
Hand in HW9, which is just problem 4.11 on
this page of LDLoS
Hand in BI23 (on an idea from Monday's class or readings)
:
Test II in class today. Make sure you are comfortable with
the material outlined on this review sheet.
Don't forget your calculator, or other favorite electronic
device, if you use one!
Today [Friday] is the last day to withdraw (with a W) from
classes.
bias, against which our strongest weapon is
randomness
voluntary sample bias
simple random sample [SRS]
Hand in BI24. This is a special one: please write a paragraph
about how you think Test II went for you. Are you perfectly content
with how it turned out? If not, what do you think was the cause of the
trouble? And what can you do next time to make things better? Do you
think the ideas you talked about in BI14 for test improvement
were effective -- were you actually able to use them?
Hand in ASE6. Please try to find something which mentions
or uses Normal distributions [which is sometimes called a
"bell[-shaped] curve"], uniformly distributed, or maybe
even some article which talks about the uses of randomness or
random numbers in modern science or computers ‐ e.g.,
sometimes this is called "using Monte Carlo methods." For this
ASE only, and only if you talk about one of these last few topics, you
may write a brief summary of something which is mostly an educational
source, and which therefore does not have live data, variables,
population, etc. Contact your instructor if you have any
concerns about what you you intend to do.
e.g., the LoLNs says that $\overline{x}$
is a good statistic for $\mu$
also, make sure survey questions are not misleading
use randomness
always aim for the [nearly impossible] SRS
wording effects
always, for heaven's sake, avoid voluntary samples
observational studies vs experiments [and
relationship to inferences about causality]
control group
confounding
lurking variable
placebo effect, placebo
The British doctor Ben Goldacre has written and spoken in
very informative and entertaining ways about the placebo effect.
His books are
Ben Goldacre at Nerdstock (this is in part about the placebo effect but also
discusses its evil twin, the nocebo effect;
warning: Ben uses some rather salty language in this
lecture, so don't watch if you are easily offended)
Hand in ASE7, which is a special one: read
this articleand any other sources you find on the same subject which are
useful (such as the research report in the Proceedings of the
National Academy of Sciences to which there is a link in that first
article), and then do as detailed an ASE as you can on this
topic, containing all the usual parts. Also include a section in
this ASE discussing the ethics of this study. Use
the ethical criteria we discussed in class and which are in the readings
from last week. As a consequence, this ASE will probably be a
fair bit longer than usual.
Today is the last day to hand in any late work for credit, even
with Homework Late Passes.
Please also hand in any unused Homework Late Passes you have left,
for course extra credit.
:
Hand in ASE8. Three options for this one:
Find one about a confidence interval for a population mean or
average (same thing). It can help to look for the phrase "margin
of error," sometimes called "sampling error" in the press. Be
careful not to get a source which is about a confidence
interval for a percentage (like election data often is, for
example), since that is not a CI for a mean (means are not
percentages).
Find one which is about a hypothesis test, as we have
done in this class. Look for "$p$-value", "null/alternative
hypothesis," other other such term[s].
Otherwise, you can just do a "free-range" ASE: pick a topic that
interests you, a nice article or webpage or whatever, which has a
clear bit of statistical content, and write up an ASE as we've been
doing all semester. [So be sure to clearly talk about the
population, variable[s], parameter[s], sample, methods,
etc.] If you go this route, please make sure you find a
one with rather a lot of interesting statistical content for which
you can show off all of your knowledge. Then make sure you do
show it off!
Hand in BI35, a special one: what do you intend to do for the
next few days to enable you to do the best you possibly can on the
final exam for this class? Be specific!
Extra Exam Week office hours, for students who still want to talk
about the course, from noon to 3pm.
:
No on campus office hours today -- but contact your instructor any
time by email for prompt help!
:
Extra Exam Week office hours, for students who still want to talk
about the course, from 2-4pm.
:
IF YOU ARE IN THE MWF 9:05-10:00AM SECTION, THEN YOUR
[COMPREHENSIVE] FINAL EXAM IS IN OUR USUAL CLASSROOM TODAY FROM
8-10:20AM. Don't forget to bring your calculator or other
favorite electronic device. You may also bring other materials to
consult during the test. See the final review
sheet for other information about the final.
below, it means that class was videoed and you can get a link by e-mailing me.
Note that if you know ahead of time that you will miss a class, you should
tell me and I will be sure to video that day for you.