As everyone should now be using the new (2012) version of the 1/P seminar, I will be removing the previous version from the lessons tab on Sept. 3rd. If you are still using the original version of the seminar, look at the videos on how to change over to the new version.
We are very excited to announce the launch of the TIA forum!
In the past, using TIA to study for exams has been a relatively solitary endeavor. You watched the videos, worked the problems, and occasionally emailed your instructor for assistance. If you prefer to learn that way, then don’t worry, you can still do it that way. Think of the forum as an additional (and optional) way to enhance your learning. You might just browse other student’s questions, and decide to give it a try later on.
Although a few TIA members have gone out of their way to interact with others by posting on the Actuarial Outpost or other public forums, the TIA forum makes it incredibly easy for all of us to interact with other members. Any time you have a question or a topic for discussion, you can immediately enter the subject forum and make your post. Everyone else that is subscribed to the seminar will see that there is a new post in that subject forum, and can respond immediately, seconding or answering your topic. Watch the short video posted in the “Before you begin” section of the course to see how the forum works.
Making your experience at TIA more interactive will result in much more powerful and effective learning. But another terrific aspect of the forum is that it will act as a growing and changing knowledge base of answered questions. As your instructor, I’ve found that I answer the same question by email many times. The forum will allow me to post answers to questions in a way that will remain readily available to all seminar users. After a while, you’ll find answers to many of your questions instantly in the forum, instead of needing an email response.
But the forums aren’t just for my answers to questions. As you probably know, there is no better way to test your knowledge than to try to answer the questions that other learners ask. You should try to answer the questions that other members post as often as you can. Other members can chime in to ask more about your answer too, and I’ll be keeping an eye on things to make sure that all the questions receive accurate and useful responses.
As always, we want your learning experience here at TIA to be a positive one. When interacting with each other on the web, please be sure to maintain a cheerful attitude and encourage your fellow learners. Feel free to immediately flag any post that you feel would discourage anyone from interacting.
The forum is open now, so go ahead and watch the introduction video and get started! You could start by introducing yourself in the “Before you begin” subject forum.
I’ve fixed 6 errors in the 2012 problems/solutions. The handouts are updated, but if you don’t want to re-download them, here are the changes:
A.1 # 15: in the example realizing the minimum, P[A'B'] should be 0, not 0.1.
A.2 # 5: P[D] = 0.274, not 0.247. I used 0.274 in the following calculations, so nothing else is affected.
A.3 #13 and #14: the exponent in the numerator should be inside the [ ].
A.4 Solution to #31, the (1/2)^2 in the denominator should be (1/2)^3
B.1 # 15 I took the wrong square root: y>a, so we want E.
B.6 # 20 theta=8.5, but the problem asks for E[X], which is 2*theta/3 = 5.7
Video solutions to B.1#15 and B.6 #20 aren’t yet updated.
We have added a CBT format to the sample exams. This means that you now have the choice of printing out the practice exams and taking them as a traditional paper and pencil exam, or you can take it on your computer in a format that is very similar to what you will see on the exam day. There are a few differences between our CBT version and the SOA’s version, but we think it is close enough that it will be good practice. In particular, you can get used to using the online exam tables.
For a demo of how to use the sample exams, we have a sample videos that you can watch in either QuickTime or WMP format. When you take a CBT sample exam, the exam will end whenever time runs out or if you click the “End” button on the review screen. At that point, your exam will be automatically scored. Note that closing the exam window will exit the exam without saving your progress or grading anything.
One feature that you should experiment with is the ability to mark questions for review. At any point during the exam, you can click the “Review” button on the bottom of the screen and that will give you the option to review either all of the exam problems, only those problems that you have marked for review, or only those problems that you haven’t answered. For example, one possible exam strategy is to make a first pass through the exam working all of the problems that you can do quickly, marking problems that you think you can do but will take a long time, and skipping problems that you don’t know how to do. Then when you are done with your first pass, you can select “Review Marked” and do the longer problems that you know how to do. After finishing that, you can review the unanswered problems that you didn’t initially know how to do and either guess or take a second stab at them.
As the CBT format is a new feature, we welcome any comments and suggestions that you may have for it. In particular, if you have taken the official exam and can let us know about some format changes that we need to make we would really appreciate it. There will always be some differences since we have to deal with different browsers and screen sizes, but we would like to minimize them. Known differences are:
- On the official CBT exam, if the problem is long enough that you need to scroll down to see all of the answer choices, you must scroll down before selecting your answer. We do not force you to do so.
- The sample CBT exam on www.beanactuary.com has the exam tables in a different order than the table on the SOA webpage. We are currently using the SOA webpage’s order, but are not sure which way you will see it.
Beginning with the January 2010 sitting, the syllabus has been changed slightly in that Pareto, Weibull, lognormal, Beta, and Chi-square distributions are no longer listed on the list of continuous distributions that you need to know. Despite this, some people have said that they still have seen questions on these distributions. In particular, this change doesn’t mean that those distributions can no longer be tested, but instead should mean that they cannot ask questions that require you to have memorized specific facts about those distributions. Other than the Chi-square distribution, I have never thought it was important to memorize anything on these distributions, so as a result, I don’t expect this to change the exam very much. There are a few Chi-square questions in the question bank that I think should be removed, but that doesn’t sound like it has happened, and there a couple lognormal questions that need to be either rephrased.
Of these 5 distributions, the Pareto and Weibull distributions are by far the most commonly tested, but the exam questions have always either given you the density (for a Pareto) or described the distribution as a transformation of an exponential (for a Weibull). In particular, the words Pareto and Weibull have never appeared on 1/P, and those questions are probably going to remain unchanged. The lognormal distribution usually comes up as a transformation of a normal, and again that is still testable as both normal distributions and transformations are testable. Finding the mean and variance of a lognormal only requires knowing the mgf of a normal, so that is still potentially testable but I think unlikely to appear. I think it is still worth watching the lognormal lesson in the seminar to see in practice how these transformations work. Likewise, the Beta distribution has almost always been tested by looking at order statistics of uniform random variables, and knowing about it can still provide you with some useful shortcuts there.
I’ve added two more sample exams and have drafted a 3rd that should be up early next week. I know that the exam date is coming up quickly and am sorry that I’m adding these somewhat at the last minute, but I figured it is better to do it now than two weeks from now.
I am going to hold online office hours Tuesday, 7/7 at 1 pm Eastern using a webinar in an experiment that we are trying. If you would like to attend, let me know and I will give you login information. Space is limited, so you should let me know relatively soon.
I’ve added a lesson to Section C.6 about the Chi-square distribution. It doesn’t come up very often on the exam, but is something that they are starting to ask about more frequently (basically going from 0 questions per exam to about 0.3 questions per exam over the past year).
I am also working on drafts of 3 more practice exams. I am hoping to get 2 of them posted next week (one earlier in the week, one later) and then the 3rd one early the following week.
I’ve added a handful more practice problems to the problems for A.1 and A.2, along with a link to the video solutions to the problems (which you can also find at http://www.theinfiniteactuary.com/?page=exams&id=137 ) I haven’t yet recorded video solutions to the new problems, but will update the solutions file with the new problems when I do so.
As you have probably noticed, we have added a few new features to the website. It now displays for you which lessons you have viewed and not viewed, which should make it easier to keep track of where you are. It will also show you what lessons have been added or updated. If the changes aren’t self-explanatory, you can watch a video explaining them that is linked on most pages, and is also at http://www.theinfiniteactuary.com/files/newvideo.wmv If you have comments and suggestions about the new look, please let me know.
One brief comment about the new look is that it only tracks the videos that you have seen since the change (i.e., since 2/15). This means that videos that you viewed earlier will say that they are unviewed. The easiest solution to this is to not care very much, but if you want to have the check marks and an accurate count of the fraction of the lessons that you have viewed, then you can trick the system by opening the videos and close the window as soon as the video starts.