Manhattan Review Blog

Monthly Archives: November 2007

Many of our non-native English speakers will find these tips useful. A mastery of euphemistical expressions can serve you well professionally. These subtle and politically correct phrases are often vague and subject to individual interpretation. They are most useful when you want to avoid being:

Direct

Negative

Obvious

Over-bearing

Here are some quick examples:

Inclusive
Meaning: With an objective view; without prejudice or bias.
Example: We should use inclusive language in our report so that it addresses to the needs of all parties.

Anomaly
Meaning: Something wrong; An unsatisfactory and unexpected inconsistency.
Example: He is usually very accurate. His last research article must be an anomaly!

Finesse
Meaning: To achieve an objective through less than honest means.
Example: Even though he is not very capable, he somehow finessed his way to top management.

Stretch The Truth

Meaning: To be dishonest
Example: When he bragged to his friends about his salary, he was stretching the truth. His actual income was much less than he said it was.

Take Something Under Advisement
Meaning: To consider something. (Often connotes that it will be ignored; used for more formal occasions.)
Example: I came up with some great ideas for the new ad campaign. My boss said she’d take my ideas under advisement. I guess she didn’t like them as much as I did.

Adjustment
Meaning: A reduction.
Example: The unexpected adjustment in my salary was announced by my boss this afternoon. I have to cut down on my expenses to make my ends meet each month.

Selective
Meaning: Dishonest
Example: He was quite selective in telling his boss the reasons the tasks didn’t get completed.

Bend the Rules
Meaning: Compromising set standards; To be flexible.
Example: The company’s vacation policy may seem strict, but our department has been known to bend the rules every now and then.

I Hear You
Meaning: I heard what you said but have a different opinion.
Example: I hear you, but I think that if we were to buy that stock we’d be taking a huge risk for little gain.

Strong Language
Meaning: Curses; swear words.
Example: We know our boss is serious when he starts to use strong language.

Careful With One’s Money
Meaning: Financial caution. Withholding financially.
Example: Our boss is very careful with his money. Sarah realized that she needed to be much more careful with her money.

Close With One’s Money
Meaning: Stingy; not generous with money.
Example: Don’t ask Chuck for a contribution to the bonus pool for all the assistants! He is so close with his money that it is not possible for him to chip in just a paltry $20.

Today we would like to take a look at the benefits and limitations of a computer adaptive test. Not that we can persuade the GMAC to bring back the paper test; Rather, we would like you to be acutely aware of the upside and downside of taking such a test in order to best acclimate yourself to the test environment.

In general, a CAT greatly increases the flexibility of test management. The key benefits include:

• Tests can be taken year around at any registered centers.
• Unofficial Scores are available immediately, expediting the B-school application process.
• Tests are individually paced so that a test-taker can choose a more suitable time of the day to take the test and special requirements for the disabled can be better accommodated.
• More accurate scores can be provided by a CAT over a wide range of abilities than by a traditional test.

For test-centers

• Minimal training of test administrators is required.
• Test security is increased because hard copy test booklets are not distributed.

For test-makers

• Test question pools and scoring method can be updated centrally and distributed at once later. Cost can be decreased while quality and speed can be improved substantially.

Despite the above advantages, computer adaptive tests have numerous limitations, and they raise several technical and procedural issues. Here we just focus on the limitations for the GMAT.

• Test-takers need to perform equally well when reading a passage, question or graph on the computer screen as on the paper. The same applies to writing an essay.
• Test-takers need to maintain a relatively high level of comfortableness with taking a test on the computer, which means that they should not make simple mistakes such as not selecting the correct answer before continuing. Other examples include that test-takers are not usually permitted to go back and change answers, requiring them to do away with their long-time paper test-taking habits. And we all know “Old habits die hard”!
• With each examinee receiving a different set of questions, there can be perceived inequities.
• There is a limited pool of test questions with the most desirable characteristics of a CAT item. This means that test security in the long run will be affected as people may try to remember the harder questions and compare notes with others. This issue can be addressed by expanding the question pool. Otherwise, it will degrade the test quality, or a longer test would be needed.

Conclusion: Practice makes perfect! Prepare with more CATs. Read long articles on your computer screen. Take mock tests in a setting similar to your test center during the same time period of a day. Reduce your response time in the areas you are best at, for example, getting your Sentence Correction time down to less than 1 minute per question. That way you can save time for the question types that you are less confidence about and achieve an overall higher total score!

Whether you are writing an admissions essay or drafting a report for work, these helpful tips are sure to create polished works:

Simple, Direct, Precise, Alive, Concise, Coherent, Convincing! Those are your targets.

1. Reduce Sentence Length to establish strong, clear meaning.
2. Order Words for Emphasis.
   • Put strong words at the beginning and at the end of a sentence.
   • Space out key words. Do NOT repeat a distinctive word unless you intend a specific effect.
   • Put odd and interesting things next to each other. Help the reader learn from contrast.
   • Do not be afraid of using small words. Big words are not always the best or most useful for getting your points across to the reader.
3. Avoid Needless Words or Stuffy Language.
   • No excess prepositional phrases
   • Use words in replace of phrases
   • No redundancy; minimize repetition
   • Watch for unnecessary adverbs such as very, really, quickly
   • No vague qualifiers, e.g. some, kind; avoid “it is”, “whether or not”…
4. Use Strong Verbs. Use passive verbs to highlight the receiver of an action.
5. Emphasize Results, Concrete Figures. Use concrete and specific details that appeal to the senses.
6. Establish Impressive Overall Style.
   • Form a pattern in your writing, but then give it a wrist to add variety.
   • Vary sentence length to set a compelling pace for the reader.

Summary:

• Convey clear, complete thoughts.
  • Do not couch too many ideas in one sentence.
• Choose every word carefully.
  • Make sure they are precise and most appropriate for the context.
• Minimize redundancy. Strive for effectiveness.

Scores, Percentiles and Their Significance

On the traditional test, all questions were worth equal points. On the GMAT CAT each question is assigned points based on the level of difficulty. There are three factors that determine your final score. The first two factors have the most bearing on your score.

1. The number of questions you answered correctly.
2. The difficulty level of each question you answered correctly.
3. The range of cognitive abilities tested by the questions answered correctly.

We discussed the third factor in our previous edition. In effect, this is measuring how well rounded you are in all areas. An individual who scores well in only a few areas will have a lower score than another individual who scored well in all areas. The way that your performance in the various tested topics is quantified is by standard deviation. The deviation between different areas is calculated and the more you deviate [i.e. higher standard deviation] between each section, the lower your GMAT score. This third factor doesn’t have as much weight on the final score as the number and difficulty of questions.

The initial (raw) score from the GMAT CAT is the ability level that corresponds to the response pattern on the administered questions. The two raw scores are combined (not the scaled scores) to form a total scaled score from 200-800. The raw score is also transformed to the Quantitative or Verbal scaled scores. For Verbal and Quantitative sections the scaled score ranges from 0 to 60.

In your score report you are also given a percentile score. This percentile means that you scored better than that percent of the testers. Percentile rankings are based on the entire GMAT test-taking population during the three most recent years. So if you got a score in the 85th percentile that means that you did better than 85% of all the people who took the test in the past three years. While GMAT scores are only a part of your overall application, a high percentile rank demonstrates that you are better than most people in the Verbal and/or Quantitative areas.

For Verbal, you will be in the 99th percentile if your scaled score is at or above 46. In comparison, it is much more competitive in Quantitative. The 99th percentile requires a scaled score of 51. This means fewer people score on Verbal than Quantitative. So make sure you don’t drag your total score down because of a mediocre performance on Verbal.

There is a degree of error with the GMAT as with all standardized tests. The standard error of difference for the total GMAT score is about 41, according to Graduate Management Admissions Council. This means that the difference between the total GMAT scores actually received by two test takers could be within 41 points above or below the difference between the test takers’ scores of true ability. The standard error of difference for the Verbal scaled score is 3.9, and for the Quantitative scaled score 4.3. Research also indicates that a test-taker will most likely earn a Total score within about 30 points of a score of true ability. Your Verbal and Quantitative scaled scores are probably within about 2.9 points of your true scores.

GMAT scores are a relatively reliable predictor of academic performance in the first year of a business school program. Studies have shown that the median correlation between GMAT scores and first-year grades was 0.41 (perfect correlation is 1.0). Comparing 0.41 to the median correlation of 0.28 between undergraduate grade point average and first-year grades, you can conclude that business schools do have a strong incentive to see good GMAT scores from applicants. Because there is a degree of error, we all should exercise caution in comparing two scores. That is why other parts of your business school application are also as crucial to your admission.

Computer-Adaptive Test Taking Strategies

Unlike the old paper-and-pencil administered GMAT of the past, the GMAT CAT is better adapted to measure your ability with fewer questions. On the old paper-and-pencil GMAT you would answer 61 questions of varying difficulty in each section. So an average test taker would breeze through the easy questions, get most of the difficult questions wrong, and get some of the medium difficulty questions right and some wrong. With the CAT, you answer only 41 questions for the Verbal section and 37 for the Quantitative section that are tailored to match your level of ability. So the average test taker is no longer wasting time answering the easy questions that he will most likely get right, nor the really difficult questions that he will most likely get wrong.

You are given a question of moderate difficulty at the beginning of the test and first question in each question type. If you answer this question correctly, then the difficulty level increases. If you answer incorrectly, the difficulty level decreases and this up-down system continues through the duration of the exam. The jump to a higher difficulty or the drop to a lower difficulty level decreases as you move through the test.

The first few questions you answer will either move you to a significantly more difficult or easy level; however, the last few questions you answer will only slightly increase or decrease in difficulty. Please also bear in mind that there is a penalty for not finishing a section. The details have not been released by the GMAC or Pearson. But for each unfinished section, the penalty is about 4x the point for an incorrectly answered question. If you run out of time, then just randomly answer the last questions, at least you have 20% of the chance of getting it right for each question. If these questions are part of the trial un-scored questions, most likely the impact on your score is not that great. (Roughly 37 out of 41 verbal questions are scored, 33 out of 37 math questions are scored. So about 4 in each section are unscored.) We need to caution you against guessing in the early stage of the test. Since your chances of guessing correctly are only 20% for each question, an incorrect choice moves you down to a less difficulty level very quickly in the beginning of the test. After a few randomly guessed wrong choices, the test assumes an appropriate level for you and it will be very hard for you to regain your momentum later as the CAT algorithm will not give you very difficult questions for you later to pile up some last minute points.

In sum, at the beginning, in as few as four questions you can move up to the highest possible level by responding correctly to all four questions, or down to the lowest possible level by responding incorrectly to all of them. This system was developed to better “zero in” on your real skill level. Think of it as adjusting a lens. You first adjust the macro-focus to ensure you are in the right range of focus, and then you adjust the micro-focus to fine tune to reach the optimal focal point. The GMAT CAT uses a complex algorithm, which we explain before, to focus in on your real skill level.

Therefore, please take particular care with the first few questions of each question type in both Verbal and Quantitative sections. Sometimes, it might be well into around the 10th question before you see a new verbal type question. Whenever you see that first question of a new type, slow down and do your best without unnecessarily spending too much time on it. Otherwise, you will have to rush through later questions. It is essentially a balancing act in which you need to pace yourself from the beginning to the end in order to maximize your score.

Computer-Adaptive Testing Algorithm

As mentioned in yesterday’s post, there are three main types of statistics required of all items in an item bank –

1. a_i – the ability of the item to discriminate between individual test-takers
2. b_i – difficulty level, and
3. c_i – the probability that the test-taker would get the question right solely by guessing.

Computer adaptive testing (“CAT”) can begin when such an item bank exists. However, two more steps are required. First, the test-maker needs to select a procedure for determining test-takers’ ability estimates based upon their performance on the tested items. Second, the test-maker needs to choose an algorithm for sequencing the set of test items to be administered to test-takers.

An ideal item pool for a computer adaptive test would be one with a large number of highly discriminating items well distributed at each ability level. The information functions for these items would appear as a series of peaked distributions across all levels of ability estimate.

The CAT algorithm is usually an iterative process with the following steps:

1. Given the currently estimated ability level of a test-taker at a given point (usually the first question is started at mid ability level), the program evaluates all the items that have not yet been administered to determine which will be the best one to administer next.In this approach, the “best” next item would be the one that provides the most information about the test-taker. Typically difficulty level of an item is the most important parameter. However, in order to be able to clearly discriminate the ability among individual test-takers, the test-maker also incorporates other factors in the item selection process on a particular exam. They include different question types (data sufficiency vs. problem solving; critical reasoning vs. sentence correction), content (e.g., algebra, ratios, combinatorics, topic and inference questions for the same reading comprehension passage, etc.), and exposure (i.e., the number of times the question has been seen by other test takers already during a given period).Demonstrating to the CAT that you can handle a variety of substantive areas in all question formats will increase your GMAT score. The greater the variance among your ability in different tested topics, the lower your score. In other words, the GMAT rewards generalists—test takers who demonstrate a broad spectrum of competencies. This approach does make sense as in a business world, being well-rounded and knowledgeable can be positively correlated to a manager’s decision-making skills and managerial ability in general.
2. The “best” next item is administered and the test-taker answers
3. The program computes a new ability estimate based on the answers to all of the previous items
4. Steps 1 through 3 are repeated until a stopping criterion is satisfied.

We will continue with our analysis on the GMAT CAT scoring system tomorrow.

So you know what the GMAT is all about, but you’re unsure exactly how answering all of those questions results in a final score that could make or break your chances for admission into business school. In this and following entries we will break down for you the system behind your score and how the test is administered to obtain that score.

Item Response Theory

Item Response Theory (IRT) is the system used by Computer-Adaptive Testing such as the GMAT CAT to determine which question is the “best” next question based on the demonstrated ability level of the test taker. It is a statistical model that relates the probability of a test-taker correctly answering a problem to characteristics of the problem and the test-taker’s true ability. It was first introduced in 1968.

The IRT model states that the probability of a correct response to item i for test-taker X is a function of ai, bi, and ci and test-taker X’s true ability. A person’s estimated true score is denoted as theta (). True score is the score a test-taker would receive on a perfectly reliable test. Since it is unavoidable for all tests to contain error, true scores are a theoretical concept; in an actual testing program, we will never know an individual’s true score. However, we can, compute an estimate of a test-taker’s true score and we can estimate the amount of error in that estimate.

P(u_i=1 | Theta_X, a_i, b_i, c_i) = c_i + (1 - c_i) / [1 + exp(-1.7 a_i (Theta_X - b_i)]

The model typically involves three parameters –

a_i defines the ability of the item to discriminate between individual test-takers,

b, is the difficulty of the item, and

c_i is the probability that the test-taker would get the question right solely by guessing.

On the GMAT, this model is used to determine your final score, i.e., where you stand on the ability scale, or, what your Theta is. For example, in the graph below, the horizontal axis is the ability scale, ranging from very low (-3.0) to very high (+3.0). When ability follows the normal curve, 68% of the test-takers will have ability between -1 and +1; 95% will be between -2.0 and +2.0. The vertical axis is the probability of responding correctly to this item.

The a_i parameter defines the slope of the curve at its inflection point. The curve would be flatter with a lower value of a_i; steeper with a higher value. Thus a_idenotes how well the item is able to discriminate between test-takers of slightly different ability (within a narrow effective range).

The b_i parameter defines the location of the curve’s inflection point along the theta scale. Lower values of b_i will shift the curve to the left; higher to the right. The b_idoes not affect the shape of the curve.

The lower asymptote is at c_i=.25. (An asymptote is a straight line or curve A to which another curve B (the one being studied) approaches closer and closer as one moves along it.) This is the probability of a correct response for test-takers with very little ability (e.g. = -2.0 or -2.6). The curve has an upper asymptote at 1.0; high ability test-takers are very likely to respond correctly.

We will continue with our analysis on the GMAT CAT scoring system tomorrow.

Some applicants receive a letter stating that they have been put on the waitlist. You too may have received such a letter. This letter means that you have the qualifications that the school is looking for, but due to other factors you have not been admitted. These factors might include you being too young, or being too experienced, or being less unique than desired, or having inconsistent track record, or not demonstrating compelling reasons for a great fit with the school. All in all, the admissions committee is not entirely convinced about your candidacy, but is willing to give you a chance.

If you have been put on waitlist by more than one school, then you should consider re-examining/strengthening your application. You should also consider applying for other schools who might take a different view on certain unchangeable elements of your application, such as you not being in the work force long enough. There are schools which may take prudent risks with young yet ambitious individuals who have a less proven track record.

To be put on the waitlist does NOT mean that you have been rejected. All programs have a limited number of applicants that they can accept each term. With the number of MBA applicants growing, the competition for admission is very intense. There are steps that you can take to improve your chances for admission.

Different Schools, Different Years, Different Policies

Some schools place an applicant on the waitlist early on in the admission process. The reason for this is that the school wishes to wait and see how the class composition is developing before making a final decision. Many times an individual who makes it to the second round of the process is competing not only against new applicants, but also against those on the waitlist. So being on the waitlist early on is not a bad thing at all. It is more like a deferment of admission. Other schools, especially those who are highly selective, rarely move people from the waitlist. This makes sense because very few people who are admitted to the top tier schools decline the offer to attend. Still other schools admit students from the waitlist who have shown improvement in their application. So each school has its own policy and procedure for the waitlist. Depending on each year’s application numbers and quality, each school may also adjust its waitlist policy a bit to better serve its admissions objective. Simply put, the “wait” for being taken off a waitlist might carry a different probability, depending on the school and the year.

Don’t Give Up!

The process is not over. You have not been rejected. There are many steps you can take to improve your chances of getting off the waitlist and being admitted. You have put so much effort into your business school application – from getting recommendation letters, to taking the GMAT and maybe the TOEFL, to writing great essays. Why would you want to give up now?

First Step – Follow instructions!

What should you do first? Follow instructions. Some schools have a strict policy against unsolicited materials from waitlist applicants. If the school specifically says that they don’t want to receive supplemental materials, then do not send them. The schools look unfavorably upon waitlist applicants who do not follow directions. What can you do if you are waitlisted at a school like this? Just wait.

If you have applied to a school that does not have such a strict policy, there are quite a few things you can do to improve your chances.

If you have applied to a school that does not have such a strict policy, there are quite a few things you can do to improve your chances:

Determine Weaknesses

The school you applied to may suggest a weakness in your application. If they have done so then take every step you can to improve your candidacy. The school may not specifically say what area you need improvement on. If you have good test scores and a strong essay, then maybe your recommendation letters were weak. Whatever your weakness may be, show the school that you have taken actions to improve.

Take Action

A school may suggest that you retake the GMAT, or maybe the TOEFL. If so then you should retake the test. Applicants who do not make effort to improve their application as instructed, show the school that they are not completely dedicated to being admitted – not a good thing. If your recommendation letters were just OK, then send in a stronger recommendation letter or a letter of support from a friend or coworker who can speak on why you would be a good fit for the school. Another thing you can do is visit the school if you have not done so already.

Follow Up

Then write a letter describing your experience and explaining how the visit has increased your interest in their program. Make sure to stay on the school’s radar. You may want to write to the school to emphasize new relevant extracurricular activities. A school would want to see improvements such as a promotion at work, a conference, or an event you organized that was successful.

Focus of the Waitlist Letter

Let the admissions committee know that you are excited to be on the waitlist and you are very interested in the school. The focus of your correspondence should be on your improvements and qualifications. You should also address steps you have taken to ameliorate any weaknesses. Demonstrate to the school how your qualifications are a perfect fit for their school. If you know that you will attend if moved from the waitlist, then let the school know that.

If you don’t hear anything in 3-5 weeks, then write again. Follow up with the school on a regular basis, but do not overdo it. Schools do not want to be bothered by waitlist applicants. Write frequently enough to keep them informed of your interest and improvements, but not so frequently that they see you as a nuisance. What you want to do is demonstrate to the school that you are making improvements since you first applied.

If you have received acceptance into a rival school, then write and clearly outline why this school should move you into the acceptance pool, and if they do so why you will definitely consider them over the rival school. The reasons need to be compelling, not just a change of heart. If the improvement in your situation is substantial, consider making a call to the admissions committee to draw prompt attention to your newly submitted Waitlist Letter.

Again, if you have nothing to add or think that by speaking to an admissions person you will talk your way in, do not contact the school. Only provide important and relevant experiences or a new perspective from supporters. You are not guaranteed to move from the waitlist, but staying in regular contact with the school to inform them of improvements and simply being perseverant will, most likely, put you closer to the front of the line.

Summary of Special Follow-up Tips

1. Thank the school for their consideration and show them that you are excited to be on the waitlist for admission. Express that the school’s philosophy and methods fit your own educational goals.
2. Demonstrate any improvements to your candidacy. (i.e. updated GMAT scores, promotions, additional responsibilities)
3. If you have not had an interview, then if you are available request an interview or campus visit.
4. If this school is your first choice, then let the school know that they are your first choice and that you will attend if admitted.
5. Let the school know of any acceptance to other rival schools. Let them know why they should move you off the list and why you would accept their school over the rival.
6. If the improvement in your situation is substantial, consider making a call to the admissions committee to draw prompt attention to your newly submitted Waitlist Letter. Remember your point of contact and try to follow up with the same person so that his/her impression about you is reinforced each time you submit additional supporting evidence.

GMAT Updates – Noticeable Trends

Based on quite a few recent student reports, the GMAT is becoming increasingly challenging, both on the math and verbal sections. Therefore thorough and serious GMAT preparation plays a crucial role in scoring high. Practice, practice and practice to get your time management under full control!

Here is a summary of recent trends, which might not be representative for all GMAT tests.

Verbal Section

Reading Comprehension: Instead of 3-4 passages, you may see 4-5 passages now with 2 science passages (non-social science) in the same exam. Some of them can be much longer or shorter than normally expected.

Takeaway Point: Gaining time from finishing Sentence Correction problems seem to become more and more inadequate. You also need to practice Reading Comprehension more diligently as it takes significantly more time and concentration to skim through each passage and jot down notes either mentally or physically.

Sentence Correction: Out of 14-15 questions in this category, you might see 3-4 fully underlined problems in the same exam.

Takeaway Point: This means that instead of zeroing in on the common errors of parts of a sentence, you should also work on most efficient and grammatically correct sentence construction to convey the underlying logic clearly. This skill also ties with your AWA practice.

Math Section

Data Sufficiency: This is an increasing number of Data Sufficiency questions, making it harder to score high, as most students have more issues with this category.

Takeaway Point: Practice more with Data Sufficiency after you get a good handle on problem solving. Do not become complacent at your math skills. Get more used to drawing conclusions based on conditions, while skipping the interim calculation. Data Sufficiency prepares you well to be a manager who is comfortable with making quick calls based on limited resources and information!

Problem Solving: The difficulty level is increasing. So study all the advanced topics as well!

1.) Start from the VERY basics: memorize all the glossaries and formulae until they come to you as a second nature.

2.) Formulate a plan with dedicated math hours per day, per week, per topic and per test category.

3.) Practice with each separate and related math conceptual areas and sub-areas at ONE time. Do NOT move on to a less relevant topic until you achieve your targeted proficiency level.

4.) If you start at least 2 or 3 months before the scheduled exam, do NOT time yourself initially to dampen your own confidence. Rather, after solving a problem, compare your solution to the one in the book, stop for a moment and think about other approaches you could have taken or intermediate steps you could have avoided to get to the same answer choice.

5.) Write down the type of mistakes you have made while practicing. Scan through the list of your common errors each time before you start to practice a series of problems to reinforce the correct approach in your mind.

6.) Start with Problem Solving first to build or rebuild a solid math foundation. Master it. Then go on to Data Sufficiency.

7.) When in Data Sufficiency, ask yourself “Is the answer definitive with ONLY one result?” If yes, then ask yourself “Which condition or combination of the conditions will lead to this ONE result. Do not get yourself confused with the question “Can this problem be solved based on the conditions given?” Often times, the answer can be derived based on the conditions; however, multiple answers can be derived, not the single result the Data Sufficiency question is typically asking for.

8.) After you studied all the conceptual topics and finished a good number of practice problems related to those topics, then start to time yourself and try to finish 37 questions within 75 minutes WITHOUT a break. If you are doing well, try to finish 40 questions within 75 minutes WITHOUT a break. Continue to increase number of questions you work with in the same time span.

9.) So you are ready now. Take a mock computer adaptive test and focus on math only. Take another one.

10.) Take an entire mock computer adaptive test with the scheduled breaks just as on the real test.

11.) Practice, practice, practice! Consult with expert instructors when you need help!

12.) You will achieve your targeted math score!

Additional Tips:

*Be aware of the relative weight the GMAT places on topics. Number properties and algebra come up again and again–master these topics before spending time on less commonly tested areas such as probability.

*Train yourself to avoid unnecessary calculations, particularly on Data Sufficiency. Remember that it is enough to know that a solution can be derived, whether or not you know the actual solution.