math stat trivial pursuit (sort of)for review (math 30)

64
MATH STAT TRIVIAL PURSUIT (SORT OF) FOR REVIEW (MATH 30)

Upload: kita

Post on 23-Feb-2016

41 views

Category:

Documents


0 download

DESCRIPTION

Math Stat Trivial Pursuit (Sort of)For Review (math 30). Colors and Categories. Blue – Basics of Estimation Pink – Properties of Estimators and Methods for Estimation Yellow – Hypothesis Testing Brown – Bayesian Methods Green – Regression - PowerPoint PPT Presentation

TRANSCRIPT

Page 1: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

MATH STAT TRIVIAL PURSUIT (SORT OF) FOR REVIEW (MATH 30)

Page 2: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

COLORS AND CATEGORIES

Blue – Basics of Estimation Pink – Properties of Estimators and Methods

for Estimation Yellow – Hypothesis Testing Brown – Bayesian Methods Green – Regression Orange – Nonparametric Procedures and

Categorical Data Analysis

Page 3: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BLUE 1 Suppose you have an estimator theta-hat,

and you want to know its bias. How is bias computed?

Page 4: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BLUE 2 How is MSE of an estimator computed?

Page 5: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BLUE 3 What is a common unbiased point estimator for a

population mean and what is its standard error?

Page 6: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BLUE 4 What is a common unbiased point estimate

of a difference in two population proportions, and what is its standard error?

Page 7: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BLUE 5 A very important result related to samples

from a normal distribution is that: The sample mean is ____________ distributed. The sample variance, appropriately scaled, is

____________ distributed. The sample mean and sample variance are

____________________.

(Fill-in all three blanks for credit).

Page 8: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BLUE 6 What are the 2 properties of pivot quantities

and what are pivots used for?

Page 9: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BLUE 7 How would you use the asymptotic normal

distribution of many unbiased point estimators to create a confidence interval for their respective parameters?

(You can just give the formula).

Hint: Think of a specific case and generalize.

Page 10: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BLUE 8 How is a t distribution formed?

Page 11: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BLUE 9 How is an F distribution formed?

Page 12: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BLUE 10 How do you form a small-sample confidence

interval for a population mean?

Page 13: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

PINK 1 If relative efficiency is computed between

two estimators, it means that both estimators were _______________, and if the numerical value of the relative efficiency is 2, then it means that the _____________ (first or second) estimator is better.

Page 14: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

PINK 2 What is the definition of consistency for an

estimator?

Bonus: What concept of convergence is this equivalent to?

Page 15: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

PINK 3 For an unbiased estimator, what is the “fast”

way of showing consistency?

Bonus: Do you remember what convergence result this was derived from?

Page 16: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

PINK 4 If you have a RS of n observations from a

distribution with unknown parameter theta, and T is sufficient for theta, what does that mean?

Page 17: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

PINK 5 What is the result you can use to show

sufficiency without resorting to computing conditional pdfs?

Page 18: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

PINK 6 What does the Rao-Blackwell Theorem say?

Bonus: What’s the fast way of finding the quantity RB refers to in the end?

Page 19: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

PINK 7 Describe how the method of moments works.

Page 20: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

PINK 8 Describe how the method of ML estimation

works.

Page 21: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

PINK 9 A main property of MLEs is that they are

_____________, which means that ….

Page 22: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

PINK 10 If an estimator is NOT admissible (i.e.

inadmissible), what does that mean?

Give an example of an inadmissible estimator.

Page 23: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

YELLOW 1 What is the difference between simple and

composite hypotheses?

Page 24: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

YELLOW 2 Describe the relationships between the two

types of error in a hypothesis test, as well as their connection to power.

Page 25: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

YELLOW 3 If you have a test statistic, you can use either

a rejection region approach or a p-value approach to determine if the null hypothesis should be rejected. What is the difference in the 2 approaches? (Describe).

Page 26: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

YELLOW 4 For the common large sample asymptotically

normal z-tests, what is the rejection region for a 2-tailed test?

Bonus: If the significance level is .05 for this test, what is the range of test statistics where you would NOT reject the null hypothesis (numerical values).

Page 27: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

YELLOW 5 How are hypothesis tests and confidence

intervals related?

Page 28: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

YELLOW 6 What is the difference between the pooled

and unpooled t-tests for 2 independent samples when considering tests for means?

Page 29: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

YELLOW 7 In order to determine which 2-sample t-test

for small sample sizes is appropriate, you might have to run a test to check for equality of _______________, and in order to control your overall significance level, you might have to use a ____________ _____________.

Page 30: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

YELLOW 8 What does the Neyman-Pearson Lemma say?

(Get the gist of it, what does it let you find, and how?)

Page 31: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

YELLOW 9 How do you determine if a most powerful test

is UMP?

Page 32: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

YELLOW 10 How do you construct a likelihood ratio test?

What is the asymptotic distribution related to LRTs?

Page 33: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BROWN 1 What is the major difference between

Frequentist and Bayesian approaches to statistics in terms of how the parameter theta is treated?

Page 34: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BROWN 2 What is the difference between a proper and

improper prior?

What is the difference between an informative and uninformative prior?

Page 35: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BROWN 3 How do you find the posterior density of

theta?

Page 36: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BROWN 4 What are conjugate priors?

Give an example of a conjugate prior.

Page 37: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BROWN 5 How would you find the Bayes estimate of:

theta theta(1-theta)

if you had the posterior density of theta?

Page 38: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BROWN 6 A Bayes estimator is ALWAYS a function of a

_______________ statistic because of the _______________ ________________.

Page 39: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BROWN 7 How is a Bayesian credible interval different

from a Frequentist confidence interval?

Page 40: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BROWN 8 Is it possible for Bayesian and Frequentists

intervals to agree? If yes, how might this happen?

Page 41: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BROWN 9 Bayesian hypothesis testing is performed using

______ ________, which are Bayesian analogues of ________ test procedures, and which can allow you to find evidence in favor of your ___________ hypothesis.

Page 42: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

BROWN 10 What are some of the issues related to

working with Bayes’ factors?

Page 43: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

GREEN 1 Relationships between two variables, X and Y

can be deterministic or ________________. Regression is used when the relationship is _______________. This means that ….

Page 44: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

GREEN 2 When first developing regression models, this

is the only constraint on the error terms.

Page 45: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

GREEN 3 If your regression model was:

Then how many parameters do you need to estimate?

3322110)( xxxYE

Page 46: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

GREEN 4 In least squares solutions for regression,

what quantity is minimized to find the solution?

(You can just give the simple LR quantity).

Page 47: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

GREEN 5 The least squares estimates are all

____________, and their variances are functions of _____________, which in turn can be estimated by _______, which is equal to (1/(n-2))SSE.

Page 48: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

GREEN 6 What is the full set of conditions on the error

terms in order to get normal sampling distributions for the parameter estimates if sigma is known?

Page 49: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

GREEN 7 Why do we end up using a t distribution for

inference about slope parameters in regression instead of a normal distribution?

Page 50: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

GREEN 8 What is the main difference between a

confidence interval for a mean response and a prediction interval for an individual response in regression?

Page 51: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

GREEN 9 How are CIs for mean responses and

prediction intervals for individual responses affected as the chosen x moves further from the mean of the x’s?

Page 52: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

GREEN 10 What is correlation and how do we test about

it?

Page 53: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

ORANGE 1 Describe the two-sample shift model.

Page 54: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

ORANGE 2 Describe how the sign test works.

Page 55: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

ORANGE 3 Describe how the signed rank test works.

Page 56: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

ORANGE 4 Describe how the Wilcoxon Rank Sum/Mann-

Whitney U test works.

Page 57: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

ORANGE 5 How does a Kolmogorov-Smirnov one-sample

test work? Is the null hypothesis in the procedure simple or composite?

Page 58: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

ORANGE 6 How does the 2-sample Kolmogorov-Smirnov

test work?

Page 59: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

ORANGE 7 When performing categorical data analysis,

the main distribution you need to understand for the theoretical setup of problems is the ______________ distribution, but the test statistics turn out to have a different distribution, which is the ________________ distribution.

Page 60: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

ORANGE 8 How is a chi-square goodness of fit test

performed? When should you perform one?

Page 61: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

ORANGE 9 How (and when) does a chi-square test of

independence work?

Page 62: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

ORANGE 10 For 2x2 tables, inference is also possible

with: _________ exact test for small sample sizes _________ ratios, which relies on an asymptotic

______ distribution for it’s natural log.

Page 63: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

Takehome Final Exam is due Friday, May 13th at 5 p.m. SHARP.

Office Hours (see front cover of exam): Monday 9-12 during my other course’s exam Tuesday 10-12 Wednesday 1-3 Thursday 1-3 Any other time by appt. – just send me an email!

REMINDER:

Page 64: Math Stat Trivial Pursuit  (Sort of)For Review (math 30)

Math dept. end of semester picnic is Saturday from 12-2 at the Alumni House

THANKS FOR A GREAT SEMESTER!