Guessing answers

In relation to the CRS software statisties, the percentage of correct answers is a very intuitive and obvious manner to assess effectiveness. However, in this study, the responses provided by the students to the questions related to the number of correct answers and the number of guessed questions were also considered. It is believed that an increase in the number of correct answers accompanied by a decrease in the number of guessed answers is demonstration of improvement and effectiveness of the corresponding method. 

Several questions present themselves immediately How good does the initial guess have to be How do we know that the procedure leads to better guesses, not worse How many steps (how long) will the procedure take How do we know when to stop These questions and others like them will play an important role in this book. You will not be surprised to leam that answers to questions like these vary from one problem to another and cannot be set down once and for all. Let us start with a famous problem in quantum mechanics blackbody radiation. 

To the frequently asked question of what could I have achieved if I had not left in 1956, I have no definite answer. I believe, however, that we should look to the future and not second-guess the past. It is the future that really counts, and the key to the future (not only in Hungary but worldwide) is a good education. Only with a good education can the younger generation succeed, but of course circumstances, desire, and ability (as well as luck) are also important. 

Where Is the Equivalence Point We have already learned how to calculate the equivalence point for the titration of a strong acid with a strong base, and for the titration of a weak acid with a strong base. We also have learned to sketch a titration curve with a minimum of calculations. Can we also locate the equivalence point without performing any calculations The answer, as you may have guessed, is often yes ... 

When Bruce presented his ten-minute solution to the graduate student instructor the next morning, the instructor remarked, You have the right answer, but 1 have never seen it done this way. I will never forget Bruce s reply, Well, 1 guess that s how they do it in the field. ... 

Another characteristic of the economic-efficiency concept IS that it does not require arbitrai y decisions by the analyst about, fur example, how coal should be evaluated compared with natural gas. The question of whether I Btu of coal is equal to 1, or perhaps 1/2, Btu of natural gas is answered directly by the market. The weightings of the marketplace, revealed in relative prices, vary with scarcity, cost of production, technology, and human preferences. Decisionmakers do not need to think about the underlying reasons, however. They need to know only current prices (and make their best guesses about future prices). 

Dr. Woodward I tried to indicate in my paper that in ammonia-hydrogen plant operation, in comparison with several other catalysts in such plants, the methanation catalyst situation is really well under control. Speaking for our company, and I would guess others, it s not a particularly active research area because we have higher priorities in catalyst development. As regards methanation catalysts for SNG, I did not discuss that today and perhaps I should let some other fellows answer first. Sulfur tolerance is one area for future development. 

A note on good practice Notice how, in the calculations, we kept all the units, writing them separately, and then canceling and multiplying them like ordinary numbers. We did not simply guess that the wavelength would turn out in meters. This procedure helps you to detect errors and ensures that your answer has the correct units. 

Two students are assigned two pure compounds to investigate. They observe that compound A boils at 37°C and compound B at 126°C. However, they run out of time to make any additional measurements, so make the following guesses about the two compounds. In each case indicate whether the guess can be justified by the data, is in error, or could be either true or false. Justify your answers, (a) Compound B has the higher molar mass, (b) Compound A is the more viscous. 

If, as a guess, the initial value of x is chosen to be xo = 4.5, convergence to the value x = 4.96511 will occur within a few iterations. On the other side, where x > 5, even wilder guesses will yield the same, correct answer. However, if xo = 4 is taken as a starting point, disaster will result. Reference to the plot of this function in Fig. 8 indicates that this point is at the maximum. As the slope is then equal to zero, the computer will yield a division by zero message for the calculation of Ax and die method fails. Of course if xq — 3 were chosen as the initial value, the procedure will converge to the root at x = 0. Clearly, the function must be plotted if such pitfalls are to be avoided. 

Robert Richards. Not only, I presume, do doctors refer to patients by their disease, but doctors refer to one another by their technical abilities, with the knife , for example, as a surgeon. If you were a hospital administrator (and I know what the answer to this question is going to be, but I d like to hear it anyway) and you have to make a decision not unlike individuals in a university department have to make a decision about hiring, and you have the knife who has that kind of technical expertise, but not noticeably is this person an ethical paragon. You have to weigh different values, and I guess... 

Compare the given value of P2 with the calculated value from step 4. If they agree, the answer is the calculated value of G2 from step 4. If they do not agree, return to step 1 with a new guess for AMal, and repeat the procedure until agreement is achieved. 

All those discussions, however, were based on considerations of the effects of multiple sources of variability, but on only a single variable. In order to compare Statistics with Chemometrics, we need to enter the multivariate domain, and so we ask the question Can ANOVA be calculated on multivariate data The answer to this question, as our long-time readers will undoubtedly guess, is of course, otherwise we wouldn t have brought it up ... 

The correct answer is 5 V. But actually, I am going to leave you guessing about the exact reason for this (if you don t already know). There are several websites dedicated to this topic, so please Google freely. It is interesting to learn that half the energy originally... 

Section I, the multiple-choice section, is machine graded. Each question has five answers to choose from. Remember, there is a penalty for guessing A of a point is taken off for each wrong answer. A student generally needs to correctly answer 50% to 60% of the multiple-choice questions to obtain a 3 on the exam. Each answer in Section II, the free-response section, is read several times by different chemistry instructors who pay great attention to consistency in grading. 

When you come to a question that seems impossible to answer, mark a large minus sign (-) next to it in your test booklet. You are penalized for wrong answers, so do not guess at this point. Move on to the next question. 

If you are able to eliminate all but two possible answers, answers such as B and E in the previous example, you may want to guess. Under these conditions, you stand a better chance of raising your score by guessing than by leaving the answer sheet blank. 

At this point you can rule out choices B, C, and D because they do not make sense. If you have forgotten how to do the problem mathematically, you should guess now you have a 50% chance of getting the answer right. 

To discourage haphazard guessing on this section of the exam, a quarter of a point is subtracted for every wrong answer, but no points are subtracted if you leave the answer blank. Even so, if you can eliminate one or more of the choices for a question, it may be to your advantage to guess. 

If you can eliminate one or more of the answers in a multiple-choice question, make an educated guess. 

Try to answer the question yourself before reading the answer choices. Guess only if you can eliminate one or more answer choices. 

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