Hypergeometric Probability Distribution
I received the following question by e-mail from someone studying for the CQE Exam. The question is from CQE Web’s reasonably priced preparation manual, QReview.
A box contains ten assemblies of which two are defective. A sample of three assemblies is selected at random. What is the probability that the two defective parts will be selected?
The Hypergeometric distribution is used to answer this question. The formula is:
Where:
N=Population size
n=sample size
D=number defective in the population
d=number defective in the sample
A=number conforming in the population
a=number conforming in the sample
To solve the problem enter the data into your calculator like this
The answer is .0667
In: Quality Engineering & CQE Exam · Tagged with: CQE
More Test Taking Advice
A couple sites worth sharing.
Tips on Taking Multiple-Choice Tests
Test taking strategies for midterms and final exams
In: Quality Engineering & CQE Exam · Tagged with: CQE
Certification Exam Strategy
I recently found a great article in a back issue of Quality Progress by James J. Rooney titled Certification Exam Tips, Trips and Traps.
The author is way more anal than I am, but it is chocked full of good advice from one who has been there. Everyone thinking of taking an ASQ exam should read it.
My exam strategy is simple.
I get the Quality Council of Indiana (QCI) Primer for the exam and read it cover to cover. I keep a running list of topics I cannot understand from the brief treatment in the Primer.
I seek out additional information from the Web or other reference material until I am completely comfortable with the BOK.
I take lots of practice exams. Sometimes I think I understand a topic, but reading a question and realizing I haven’t a clue where to begin is all the proof I need to start looking for additional information. I use my incorrect answers (and wild guesses) to continue focusing my study.
On exam day, I wake up early and treat my self to my favorite lite breakfast. I get my favorite beverage and snack, and arrive at the exam site early to organize my work area. I take all my reference material, but only plan on using one or two of them, the others are there for comfort. I also take a full box of sharp pencils; at least 50. I like to be over prepared. And, if I can give a pencil to someone who forgot his, that’s more good karma coming my way. I do not study at all the morning of the exam. Rather, I try to enter a Zen-like peaceful state.
I read thru the exam three times. The first time, I read every question answering only the ones I am >80% confident I know the answer. I also mark the questions that I could answer if I were sure of the definition of one or two key words. The second read, I look up every definition for the marked questions. The third time thru I do the math/statistics questions, I did not answer in the first two reads. In the time left, I answer all of the remaining questions. If I have time I look them up, if not I just guess.
WARNING: frequently check your answer sheet to ensure your answer number matches the question number.
In: Quality Engineering & CQE Exam · Tagged with: CQE
CQE Refresher Courses
The CQE exam date is fast approaching. Sign up for the CQE refresher course, while you still can. They are typically sponsored by your local ASQ division, and run the weeks leading up to the exam.
Reasons to take a refresher course.
Accountability: ASQ division 0905 runs refresher courses the 6 Saturdays prior to the exam date. Each class lasts four hours. That’s 24 hours of study. I always here 100 hours of study is recommended, but I don’t know from what authority. Knowing that an instructor will be encouraging you each week helps motivate you to study otherwise very dry material.
Expert Advice: Minimum requirements to be an instructor usually include passing the CQE exam. You will learn test taking techniques and ways to solve statistics and probability problems quickly. Your instructor is a resource for specific questions that are giving you trouble. And, you can even get advice on using your calculator.
Networking: Each week you will be building relationships with other quality professionals. Since most jobs are landed because you know someone, and since most people change jobs often throughout their lives. It may be wise to stay in contact.
In: Quality Engineering & CQE Exam · Tagged with: CQE
Simple Work Instructions and Procedures
This week, Miki Saxon at Leadership Turn, reminded me of a one of my favorite quotes by Visa Founder Dee Hock.
“Simple clear purpose and principles give rise to complex intelligent behavior. Complex rules and regulations give rise to simple stupid behavior.”
I am a big fan of simple work instructions and procedures. Like a good resume, they should be short, one to two pages max, or no one will read them. There are exceptions to this rule, but they should be few, and always it should be pictures, not words creating the length.
Many times, procedures are intentionally written long by quality professionals attempting to improve the process without leaving their desk. Processes must first be improved by solid improvement techniques, then documented in a simple, specific work instruction to ensure standardization, and to help ensure the improvement is sustained.
Another reason procedures grow long is due to a widely accepted fallacy that procedures are best left vague. “You don’t want to tie yourself down,” they say, “that’s just asking for audit trouble.” “No,” I say, “writing vague procedures that offer little direction and which no one reads anyway, that is asking for audit trouble.” It takes a lot of words to turn vagueness into something that looks like a procedure.
On the other hand being meaningfully specific takes only a few words, often along side pictures or screen captures. The best approach to write simple specific procedures is for the quality professional to work with the affected employees and together document the right way to do a thing. Then, the simple one to two page procedure can become the norm.
In: General Quality Topics · Tagged with: procedure, simple, work instruction
Page Updates: Week Ending March 28, 2009
Added the following links, where appropriate, to the CQE and CQT Help pages.
Process capability indexes Cp and Cpk. And added Cpk vs. Ppk.
Also added Calculator FAQ and this ref. card for the TI-30XS Multiview statistics variables.
I value your suggestions. If you are taking an ASQ exam and want me to add specific content, please comment below, or send an email with your request to brn@brianrnichols.com
In: Uncategorized
Resolving Team Conflict
There are two types of conflict; one is good the other is corrosive. Luckily, there is a strategy to resolve both.
Purpose driven conflict is constructive. It is conflict resulting from two or more highly motivated individuals and their desire for the success of the organization. This conflict is constructive and if harnessed leads to synergy and innovation.
Personality conflict is the ugly product of the worst in human nature. Politics, envy, and plain dislike can lead to serious conflict. Many times personal conflict remains in the background; this is conflict at its worst. Personal slights, gossip, rumormongering, reputation destruction take a toll on all involved.
Steps To Resolving Conflict
Be the Mediator – Rarely does conflict resolve itself. A mediator is required. The team leader often plays this role, but anyone can.
Confront the Conflict – Conflict that is out in the open and identified is easier to deal with. Also, an intentional break from the team’s business to start focusing on conflict means the team then has to end the conflict discussion to get back to work. Getting back to work has the psychological effect of bringing closure to the conflict.
Take a Break (if Needed) – Sometimes tempers prevent individuals from listening. When any one of the parties of conflict refuses to listen, a break is needed. Sometimes a five min. break will do, sometimes it takes sleeping on the issue before progress can be made.
Win-Win or No Deal – No one said it better than Steven Covey. I’ll make it real simple, when everybody wins there is no conflict.
Agree to Move Forward – When conflict is resolved and the team agrees to move forward, the team will be stronger because of the shared experience.
In: General Quality Topics · Tagged with: conflict
TI-30XS Multiview: Don’t take the CQE without it
ASQ is crazy to prohibit the use of graphing calculators on their exams. All but the absolute most expensive calculators are allowed on SAT’s, and any professional has access to much more powerful tools on their computer. Strictly following the ASQ rules, even the TI-73 which is marketed to 6th graders is outlawed.
The main reason to use a graphing calculator is the large display, font that looks like the textbook, and list layout. My primary calculator is the TI-89, specifically banned by the ASQ rules. I don’t know how to program the thing. Even if I could I cannot imagine it helping me. Anyone nerd enough to program a calculator will have no problem with math on ASQ exams.
That brings me to the TI-30XS Multiview. It has the pretty MATHPRINT font, a larger screen, and data can be entered in lists for easy calculation of one and two variable statistics. The interface is intuitive, the user manual easy to understand, and its less than $20. If it had unit conversion, I’d sell my graphing calculator on eBay. I use MiniTab and Excel for graphs.
The bottom line, Don’t take an ASQ exam without it.
In: Quality Engineering & CQE Exam · Tagged with: CQE, CQT, quality engineer, quality technician