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My Midterm Exam Prep Seminar for Stat 2000 is Sunday, October 26. It is NOT on campus. It is held at Canadian Mennonite University, on the SOUTH side of Grant Ave., at 600 Shaftesbury Blvd. In the Lecture Hall. It costs $20 if you bring my book to the
seminar, or $40 without a book.
Did you read my tips on how to study and learn Stat 2000? If not, here is a link to those important suggestions: Did you read my Calculator Tips? If not, here is a link to those important suggestions: Study Lesson 6: Introduction to Probability and Lesson 7: Discrete Probability Distributions in my book (if you have it) to prepare for this assignment.
Please note: Only the current edition of my book has Lesson 6 above. It is in volume 1. If you have an older edition of my book, you are missing a very important lesson that has taken prominence in the course in the last couple of years. Lesson 7 is in volume 2 of my book. That was the former Lesson 6 in earlier editions. I strongly encourage you to consider buying at least
volume 1 of my new book. If you have a recent older edition of my book, that may be sufficient for you to avoid purchasing volume 2 of my new book.
I am always appreciative of students who purchase the new edition of my book each year, rather than using used copies. Book sales are what helps me fund the free services I offer such as these tips.
Remember my advice in the tips above. Don't start working on the assignment too soon. Study and learn the lesson first, and use the assignment to test your knowledge. Of course, always seek out assistance from my book, your course notes, etc. if you ever hit a question you don't understand, but try not to be learning things as you do an assignment. Learn first, then put your learning to the
test.
Exception: Always do any JMP stuff open-book. Have my tips in front of you, and let me guide you step-by-step through any JMP stuff. JMP is just "busy" work. The sooner you get it done and can move on to productive things like understanding the concepts and interpreting the JMP outputs, the better off you will be.
Don't have my book? You can download a free sample of my book and audio lectures containing Lesson 3:
A Warning about StatsPortal
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Make sure that you are using Firefox for your browser. Don't even use Internet Explorer. It actually also has some glitches in the HTML editor boxes.
Do note that every time you exit a question in StatsPortal, the next time you return to it, the data may very
well change. Do not press the "back-up" button on your browser in a question. That, too, will change the data. When you are prepared to actually do a question, open the link, keep it open, and do not close it until you have submitted your answers. Be sure to press "Save Answers" once you have done any calculations and entered any information to ensure the data does not change and force you to start over again.
After you submit the answer to a question,
if you have been marked wrong on any parts, be sure that you write down the correct answers before you exit the screen (or grab a screen shot). To try a second attempt at the question do not click the link to the question again, that will change the data and you will have to start all over again. Also, DO NOT click "try again" or make a "second attempt." That will also reset the data.
Instead, exit back to the home screen where they show the
links for all the different questions on the assignment. Where it shows the tries for a question on the right side of your screen, you should see the "1" grayed out, showing that you have had 1 attempt. Click the number "2" to get your second attempt with the same data. That way you can enter the answers you already know are correct and focus on correcting your mistakes.
You should also have already downloaded the JMP statistical software which was
provided with either one of the course options for StatsPortal as mentioned in your course outline.
Make sure you have gone through Assignment 0 completely to learn how to use the interface. I also suggest you print out a copy of question 8 in Assignment 0 (Long Answer Questions - Part 3) so that you have the steps for saving and uploading files into the HTML editor in front of you.
I cover the Binomial Distribution in Lesson 7. If you are ever asked to decide if a particular situation is binomial or not, remember, to be binomial, four conditions must be satisfied: - There must be a fixed number of trials, n.
- Each trial can have only two possible outcomes, success or failure, and the probability of success on each trial must have a constant value, p.
- Each trial must be independent.
- X, the number of successes, is a discrete random variable
where X = 0, 1, 2, ... n.
Hints: If you are reading off numbers from a randomly selected row in the random number table, note that every row has 40 digits. That is like 40 trials looking for whatever digit you may be looking for. What is the probability that, at any moment on the table, the next digit is a 0, or a 1, or a 2, etc.. If you are selecting objects, are you sampling with replacement (independent trials) or without
replacement (dependent trials)?
Question 2: Newspaper Probabilities
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This is best solved using a three-circle Venn Diagram, similar to my Lesson 6, question 18. Make sure you have studied Lesson 6 thoroughly before attempting this question. You have lots of practice in the lesson and
determining if events are independent, disjoint or neither. There are also several conditional probabilities in this question.
Part (f) should really read without doing any further calculations, because it is only through all the calculations did in order to answer part (e), that you are able to answer part (f) without any more work. But, honestly, if you don't
see how, and need to use your conditional probability method to solve it, go for it. No one knows what calculations you did, if any.
Question 3: Card Probabilities
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I am not sure why this is called "Card Probabilities" when it is about balls. You can use a Two-way table to list all the outcomes in your sample space for part (a), but, be careful! You are sampling without replacement, so some of
the outcomes must be eliminated. For example, if you make columns labeled 1,2,2,3 and 4 and also label the rows like that, your will get the outcome 11, for example, but that is impossible since, if 1 was picked the first time, it is unavailable for selection the second time.
It might be easier to just assume you picked 1 first, then what could the second ball be? What if you picked 2 first, what could the
second ball be? What if you picked the other 2 first? The 3 first? The 4 first?
My Lesson 6, question 13 may be of some help in understanding how to do parts (b) and (c).
Note, the expected value is the mean value. I show you how to compute mean and variance of X in Lesson 6, question 1
and I also do it more thoroughly in Lesson 7, questions 1 to 3.
Question 4: Sum/Difference of Normal
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You have two normal distributions, X and Y. You can use the properties of mean and variance I teach at the start of Lesson 4 to work out the mean and variance of X + Y. Since X and Y are both normal distributions, X + Y is also normal.
You can also compute the mean and variance for X - Y. You also know that X - Y is normal.
Of course, to change your score into a z-score, you will have to use the standardizing formula you first learned in Stat 1000, z = (x - mu)/sigma or z = (x - μ)/σ.
Part (b) wants X < Y. Rewrite that as X - Y < 0.
Part (c) wants X = Y. Rewrite that as X - Y =
0. Think carefully! What are you shading on your bell curve.?
Question 5: Traffic Light Probabilities
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I introduce the formula for mean and standard deviation of a binomial distribution in my Lesson 7, question 10. Be careful that you are using the correct n and p for each question since they keep switching which colour of light and how many days
they are talking about. Note that n is the total number of intersections he/she has encountered during the time period.
Question 6: Binomial Type I & Type II Error
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I teach this in Lesson 7 in the " Hypothesis Testing Revisited" section. Note that you can use Table C to solve the probabilities more quickly. My question 19 is very similar.
Question 7: Poisson Crickets
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Standard Poisson stuff as taught in Lesson 7. Make sure you are using the correct value for lambda.
Question 8: Poisson Telemarketer
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Standard Poisson stuff as taught in Lesson 7. Make sure you are using the correct value for lambda. |
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