Tài liệu GRE_ Computer Science Test docx

GRADUATE RECORD EXAMINATIONS® Computer Science Test Practice Book This practice book contains Ⅲ one actual full-length GRE Computer Science Test Ⅲ test-taking strategies Become familiar with Ⅲ test structure and content Ⅲ test instructions and answering procedures Compare your practice test results with the performance of those who took the test at a GRE administration Visit GRE Online at www.gre.org Listening Learning Leading This book is provided FREE with test registration by the Graduate Record Examinations Board Note to Test Takers: Keep this practice book until you receive your score report The book contains important information about content specifications and scoring Copyright © 2004 by Educational Testing Service All rights reserved EDUCATIONAL TESTING SERVICE, ETS, the ETS logos, GRADUATE RECORD EXAMINATIONS, and GRE are registered trademarks of Educational Testing Service Table of Contents Purpose of the GRE Subject Tests Development of the Subject Tests Content of the Computer Science Test Preparing for a Subject Test Test-Taking Strategies What Your Scores Mean Practice GRE Computer Science Test Scoring Your Subject Test 47 Evaluating Your Performance .50 Answer Sheet .51 Purpose of the GRE Subject Tests The GRE Subject Tests are designed to help graduate school admission committees and fellowship sponsors assess the qualifications of applicants in specific fields of study The tests also provide you with an assessment of your own qualifications Scores on the tests are intended to indicate knowledge of the subject matter emphasized in many undergraduate programs as preparation for graduate study Because past achievement is usually a good indicator of future performance, the scores are helpful in predicting success in graduate study Because the tests are standardized, the test scores permit comparison of students from different institutions with different undergraduate programs For some Subject Tests, subscores are provided in addition to the total score; these subscores indicate the strengths and weaknesses of your preparation, and they may help you plan future studies The GRE Board recommends that scores on the Subject Tests be considered in conjunction with other relevant information about applicants Because numerous factors influence success in graduate school, reliance on a single measure to predict success is not advisable Other indicators of competence typically include undergraduate transcripts showing courses taken and grades earned, letters of recommendation, the GRE Writing Assessment score, and GRE General Test scores For information about the appropriate use of GRE scores, write to GRE Program, Educational Testing Service, Mail Stop 57-L, Princeton, NJ 08541, or visit our Web site at www.gre.org/codelst.html Development of the Subject Tests Each new edition of a Subject Test is developed by a committee of examiners composed of professors in the subject who are on undergraduate and graduate faculties in different types of institutions and in different regions of the United States and Canada In selecting members for each committee, the GRE Program seeks the advice of the appropriate professional associations in the subject The content and scope of each test are specified and reviewed periodically by the committee of examiners Test questions are written by the committee and by other faculty who are also subject-matter specialists and by subject-matter specialists at ETS All questions proposed for the test are reviewed by the committee and revised as necessary The accepted questions are assembled into a test in accordance with the content specifications developed by the committee to ensure adequate coverage of the various aspects of the field and, at the same time, to prevent overemphasis on any single topic The entire test is then reviewed and approved by the committee COMPUTER SCIENCE TEST PRACTICE BOOK Subject-matter and measurement specialists on the ETS staff assist the committee, providing information and advice about methods of test construction and helping to prepare the questions and assemble the test In addition, each test question is reviewed to eliminate language, symbols, or content considered potentially offensive, inappropriate for major subgroups of the testtaking population, or likely to perpetuate any negative attitude that may be conveyed to these subgroups The test as a whole is also reviewed to ensure that the test questions, where applicable, include an appropriate balance of people in different groups and different roles Because of the diversity of undergraduate curricula, it is not possible for a single test to cover all the material you may have studied The examiners, therefore, select questions that test the basic knowledge and skills most important for successful graduate study in the particular field The committee keeps the test up-to-date by regularly developing new editions and revising existing editions In this way, the test content changes steadily but gradually, much like most curricula In addition, curriculum surveys are conducted periodically to ensure that the content of a test reflects what is currently being taught in the undergraduate curriculum After a new edition of a Subject Test is first administered, examinees’ responses to each test question are analyzed in a variety of ways to determine whether each question functioned as expected These analyses may reveal that a question is ambiguous, requires knowledge beyond the scope of the test, or is inappropriate for the total group or a particular subgroup of examinees taking the test Answers to such questions are not used in computing scores Following this analysis, the new test edition is equated to an existing test edition In the equating process, statistical methods are used to assess the difficulty of the new test Then scores are adjusted so that examinees who took a difficult edition of the test are not penalized, and examinees who took an easier edition of the test not have an advantage Variations in the number of questions in the different editions of the test are also taken into account in this process Scores on the Subject Tests are reported as threedigit scaled scores with the third digit always zero The maximum possible range for all Subject Test total scores is from 200 to 990 The actual range of scores for a particular Subject Test, however, may be smaller The maximum possible range of Subject Test subscores is 20 to 99; however, the actual range of subscores for any test or test edition may be smaller than 20 to 99 Subject Test score interpretive information is provided in Interpreting Your GRE Scores, which you will receive with your GRE score report, and on the GRE Web site at www.gre.org/codelst.html Content of the Computer Science Subject Test The test consists of about 70 multiple-choice questions, some of which are grouped in sets and based on such materials as diagrams, graphs, and program fragments The approximate distribution of questions in each edition of the test according to content categories is indicated by the following outline The percentages given are approximate; actual percentages will vary slightly from one edition of the test to another I SOFTWARE SYSTEMS AND METHODOLOGY — 40% A Data organization Data types Data structures and implementation techniques B Program control and structure Iteration and recursion Procedures, functions, methods, and exception handlers Concurrency, communication, and synchronization C Programming languages and notation Constructs for data organization and program control Scope, binding, and parameter passing Expression evaluation COMPUTER SCIENCE TEST PRACTICE BOOK Upper and lower bounds on the complexity of specific problems Computational complexity, including NPcompleteness B Automata and language theory Models of computation (finite automata, Turing machines) Formal languages and grammars (regular and context-free) Decidability C Discrete structures Mathematical logic Elementary combinatorics and graph theory Discrete probability, recurrence relations, and number theory D Software engineering Formal specifications and assertions Verification techniques Software development models, patterns, and tools E Systems Compilers, interpreters, and run-time systems Operating systems, including resource management and protection/security Networking, Internet, and distributed systems Databases System analysis and development tools II COMPUTER ORGANIZATION AND ARCHITECTURE — 15% A Digital logic design Implementation of combinational and sequential circuits Optimization and analysis B Processors and control units Instruction sets Computer arithmetic and number representation Register and ALU organization Data paths and control sequencing C Memories and their hierarchies Performance, implementation, and management Cache, main, and secondary storage Virtual memory, paging, and segmentation D Networking and communications Interconnect structures (e.g., buses, switches, routers) I/O systems and protocols Synchronization E High-performance architectures Pipelining superscalar and out-of-order execution processors Parallel and distributed architectures III THEORY AND MATHEMATICAL BACKGROUND — 40% A Algorithms and complexity Exact and asymptotic analysis of specific algorithms Algorithmic design techniques (e.g., greedy, dynamic programming, divide and conquer) IV Other Topics — 5% Example areas include numerical analysis, artificial intelligence, computer graphics, cryptography, security, and social issues Note: Students are assumed to have a mathematical background in the areas of calculus and linear algebra as applied to computer science Preparing for a Subject Test GRE Subject Test questions are designed to measure skills and knowledge gained over a long period of time Although you might increase your scores to some extent through preparation a few weeks or months before you take the test, last-minute cramming is unlikely to be of further help The following information may be helpful ▪ A general review of your college courses is probably the best preparation for the test However, the test covers a broad range of subject matter, and no one is expected to be familiar with the content of every question COMPUTER SCIENCE TEST PRACTICE BOOK Ⅲ Use this practice book to become familiar with the types of questions in the GRE Computer Science Test, paying special attention to the directions If you thoroughly understand the directions before you take the test, you will have more time during the test to focus on the questions themselves Test-Taking Strategies The questions in the practice test in this book illustrate the types of multiple-choice questions in the test When you take the test, you will mark your answers on a separate machine-scorable answer sheet Total testing time is two hours and fifty minutes; there are no separately timed sections Following are some general test-taking strategies you may want to consider Ⅲ Read the test directions carefully, and work as rapidly as you can without being careless For each question, choose the best answer from the available options Ⅲ All questions are of equal value; not waste time pondering individual questions you find extremely difficult or unfamiliar Ⅲ You may want to work through the test quite rapidly, first answering only the questions about which you feel confident, then going back and answering questions that require more thought, and concluding with the most difficult questions if there is time Ⅲ If you decide to change an answer, make sure you completely erase it and fill in the oval corresponding to your desired answer Ⅲ Questions for which you mark no answer or more than one answer are not counted in scoring Ⅲ As a correction for haphazard guessing, onefourth of the number of questions you answer incorrectly is subtracted from the number of questions you answer correctly It is improbable that mere guessing will improve your score significantly; it may even lower your score If, however, you are not certain of the correct answer but have some knowledge of the question and are able to eliminate one or more of the answer choices, your chance of getting the right answer is improved, and it may be to your advantage to answer the question Ⅲ Record all answers on your answer sheet Answers recorded in your test book will not be counted Ⅲ Do not wait until the last five minutes of a testing session to record answers on your answer sheet What Your Scores Mean Your raw score–that is, the number of questions you answered correctly minus one-fourth of the number you answered incorrectly–is converted to the scaled score that is reported This conversion ensures that a scaled score reported for any edition of a Subject Test is comparable to the same scaled score earned on any other edition of the same test Thus, equal scaled scores on a particular Subject Test indicate essentially equal levels of performance regardless of the test edition taken Test scores should be compared only with other scores on the same Subject Test (For example, a 680 on the Computer Science Test is not equivalent to a 680 on the Mathematics Test.) Before taking the test, you may find it useful to know approximately what raw scores would be required to obtain a certain scaled score Several factors influence the conversion of your raw score to your scaled score, such as the difficulty of the test edition and the number of test questions included in the computation of your raw score Based on recent editions of the Computer Science Test, the table on the next page gives the range of raw scores associated with selected scaled scores for three different test editions (Note that when the number of scored questions for a given test is greater than the number of possible scaled scores, it is likely that two or more raw scores will convert to the same scaled score.) The three test editions in the table that follows were selected to reflect varying degrees of difficulty Examinees should note that future test editions may be somewhat more or less difficult than the test editions illustrated in the table COMPUTER SCIENCE TEST PRACTICE BOOK Range of Raw Scores* Needed to Earn Selected Scaled Scores on Three Computer Science Test Editions That Differ in Difficulty Raw Scores Scaled Score Form A Form B Form C 800 47 41-42 37-38 700 31 27 22-23 600 16-17 15 11 500 3-4 Number of Questions Used to Compute Raw Score 70 69 67 *Raw Score = Number of correct answers minus one-fourth the number of incorrect answers, rounded to the nearest integer For a particular test edition, there are many ways to earn the same raw score For example, on the edition listed above as “Form A,” a raw score of 31 would earn a scaled score of 700 Below are a few of the possible ways in which a scaled score of 700 could be earned on that edition Examples of Ways to Earn a Scaled Score of 700 on the Edition Labeled as “Form A” Number of Questions Questions Questions Questions Used Answered Answered Not to Compute Raw Score Correctly Incorrectly Answered Raw Score 31 31 39 70 31 34 12 24 70 31 38 28 70 COMPUTER SCIENCE TEST PRACTICE BOOK Practice Test To become familiar with how the administration will be conducted at the test center, first remove the answer sheet (pages 51 and 52) Then go to the back cover of the test book (page 46) and follow the instructions for completing the identification areas of the answer sheet When you are ready to begin the test, note the time and begin marking your answers on the answer sheet COMPUTER SCIENCE TEST PRACTICE BOOK FORM GR0329 29 GRADUATE RECORD EXAMINATIONS® COMPUTER SCIENCE TEST Do not break the seal until you are told to so The contents of this test are confidential Disclosure or reproduction of any portion of it is prohibited THIS TEST BOOK MUST NOT BE TAKEN FROM THE ROOM Copyright © 2002, 2003 by Educational Testing Service All rights reserved GRE, GRADUATE RECORD EXAMINATIONS, ETS, EDUCATIONAL TESTING SERVICE and the ETS logos are registered trademarks of Educational Testing Service COMPUTER SCIENCE TEST Time—170 minutes 70 Questions Notation, Conventions, and Definitions: In this test a reading knowledge of modern programming languages is assumed The following notational conventions and definitions are used All numbers are assumed to be written in decimal notation unless otherwise indicated x denotes the greatest integer that is less than or equal to x x denotes the least integer that is greater than or equal to x g (n) = O( f (n)) denotes “ g (n) has order at most f (n)” and means that there exist positive constants C and N such that g(n) £ Cf (n) for all n > N g (n) = W ( f (n)) denotes “g(n) has order at least f (n) ” and for this test means that there exist positive constants C and N such that g (n) ≥ Cf (n) for all n > N g (n) = Q( f (n)) denotes “ g (n) has the same order as f (n) ” and means that there exist positive constants C1 , C2 , and N such that C1 f (n) £ g(n) £ C f (n) for all n > N denotes “there exists.” denotes “for all.” denotes “implies;” … is also used to denote “implies;” and fi is also used to denote “implies.” denotes “not”; “ A ” is also used as meaning “ ÿ A ” ⁄ $ " Ỉ ÿ denotes “inclusive or”; + also denote “inclusive or,” e.g., P + Q can denote “ P or Q ” ≈ denotes “exclusive or.” Ÿ denotes “and”; also, juxtaposition of statements can denote “and,” e.g., PQ can denote “P and Q.” A boolean formula is satisfiable if it is true under some assignment of boolean values for its variables A boolean formula is a tautology (or is valid) if it is true under all assignments of boolean values for its variables ∆ denotes the empty set If A and B denote sets, then: A » B is the set of all elements that are in A or in B or in both; A « B is the set of all elements that are in both A and B; A is the set of all elements not in A that are in some specified universal set A is the cardinality of A In a string expression, if S and T denote strings or sets of strings, then: An empty string is denoted by e or by L ; ST denotes the concatenation of S and T ; S + T denotes S » T or {S , T} , depending on context; S n denotes SS S ; n factors S* denotes e + S + S + S + ; S + denotes S + S + S + Unauthorized copying or reuse of any part of this page is illegal 10 57 Company X shipped computer chips, of which was defective, and Company Y shipped computer chips, of which were defective One computer chip is to be chosen uniformly at random from the chips shipped by the companies If the chosen chip is found to be defective, what is the probability that the chip came from Company Y ? (A) (B) (C) (D) (E) 58 An Euler circuit of an undirected graph is a circuit in which each edge of the graph appears exactly once Which of the following undirected graphs must have an Euler circuit? I A complete graph with 12 vertices II A complete graph with 13 vertices III A tree with 13 vertices (A) I only (B) II only (C) III only (D) I and II (E) I and III 59 Consider the following two languages x has equally many a’s and b’sp k = k x Œ{a, b, c}* x has equally many a’s, b’s, and c’sp L1 = x Œ{a, b}* L2 Which of the following is true about L1 and L ? (A) L1 and L are both regular (B) L1 is regular, and L is context-free but not regular (C) Neither L1 nor L is regular, but both are context-free (D) L1 is context-free but not regular, and L is not context-free (E) Neither L1 nor L is context-free Unauthorized copying or reuse of any part of this page is illegal GO ON TO THE NEXT PAGE 39 60 Consider the following possible data structures for a set of n distinct integers I A min-heap II An array of length n sorted in increasing order III A balanced binary search tree For which of these data structures is the number of steps needed to find and remove the 7th largest element O(log n) in the worst case? (A) I only (B) II only (C) I and II (D) I and III (E) II and III 61 Which of the following problems is (are) decidable? I Given a (finite) string w, is w a prefix of the decimal expansion of p ? II Given a program and an input, is the program’s output the decimal expansion of p ? III Given a program that takes as input a prefix of the decimal expansion of p , is the program’s output always the same for every prefix? (A) I only (B) II only (C) III only (D) I and II only (E) I, II, and III Unauthorized copying or reuse of any part of this page is illegal 40 GO ON TO THE NEXT PAGE 62 Which of the following problems would have polynomial time algorithms if it is assumed that P π NP ? I Given a combinational circuit with n inputs and m outputs and n gates, where each gate is either AND, OR, or NOT, and given m values c1 , , cm in 0, , either find a string of n input values b1 , , bn in 0, that would produce c1, , cm as output or determine that c1, , cm is not a possible output of the circuit k p k p II Given an n by n matrix A with rational number entries, either find the exact inverse A −1 of A or determine that A −1 does not exist (Assume that each rational number is expressed as a pair a/b of integers b π , where a and b are expressed in binary notation.) a f III Given a directed graph with nodes numbered 1, 2, , n, and given positive integer weights assigned to the edges, either find the length of a shortest path from node to node n or determine that no such path exists (Here the length of a path is the sum of the lengths of the edge weights on the path.) (A) I only (B) II only (C) III only (D) I and II (E) II and III 63 Which of the following characteristics of a programming language is best specified using a context-free grammar? (A) Identifier length (B) Maximum level of nesting (C) Operator precedence (D) Type compatibility (E) Type conversion Unauthorized copying or reuse of any part of this page is illegal GO ON TO THE NEXT PAGE 41 64 Consider the following function f(k) { x = 2; for i = to k x = x * x; return x; } If n and k are positive integers, then the least value of k such that f(k) > n is approximately (B) log2 n (A) log2 (log2 n) (C) n (D) n log2 n (E) n 65 Let T be a depth-first search tree of a connected undirected graph G For each vertex v of T, let pre(v) be the number of nodes visited up to and including v during a preorder traversal of T , and post (v) be the number of nodes visited up to and including v during a postorder traversal of T The lowest common ancestor of vertices u and v in T is a vertex w of T such that w is an ancestor of both u and v, and no child of w is an ancestor of both u and v Let (u, v ) be an edge in G that is not in T, such that pre(u) < pre(v) Which of the following statements about u and v must be true? I post (u) < post(v) II u is an ancestor of v in T III If w is the lowest common ancestor of u and v in T, then w = u (A) I only (B) II only Unauthorized copying or reuse of any part of this page is illegal 42 (C) III only (D) I and II (E) II and III GO ON TO THE NEXT PAGE 66 Consider languages L and L1, each over the alphabet {a, b}, where k p L1 = w w contains some x Œ L as a substring Which of the following must be true about L and L1 ? I If L is regular, then L1 is regular II If L is context-free, then L1 is context-free III If L is recursive, then L1 is recursive (A) I only (B) III only (C) I and III only (D) II and III only (E) I, II, and III 67 For each nonnegative integer n, let Rn be the greatest possible number of regions into which the plane can be partitioned by n straight lines For example, R0 = and R1 = Then Rn has order af (B) Θan log nf (C) Θdn i (D) Θd2 i (E) Θan !f (A) Θ n n Unauthorized copying or reuse of any part of this page is illegal GO ON TO THE NEXT PAGE 43 68 Which of the following comes closest to being a perfectly secure encryption scheme? (A) The Caesar Cipher, a substitution cipher (B) DES (Data Encryption Standard), a symmetric-key algorithm (C) Enigma, a transposition cipher (D) One-time pad (E) RSA, a public-key algorithm 69 Suppose Q and R are languages Assuming P π NP, which of the following implies that R is not in P ? (A) R is in NP (B) Q is in NP and Q is polynomial-time reducible to R (C) Q is in NP and R is polynomial-time reducible to Q (D) Q is NP-complete and Q is polynomial-time reducible to R (E) Q is NP-complete and R is polynomial-time reducible to Q Unauthorized copying or reuse of any part of this page is illegal 44 GO ON TO THE NEXT PAGE 70 Let N be the set of all natural numbers Which of the following sets are countable? k p I The set of all functions from N to 0, k p II The set of all functions from 0, to N III The largest subset of N (A) None (B) I and II only (C) I and III only (D) II and III only (E) I, II, and III STOP If you finish before time is called, you may check your work on this test Unauthorized copying or reuse of any part of this page is illegal 45 NOTE: To ensure prompt processing of test results, it is important that you fill in the blanks exactly as directed I SUBJECT TEST A Print and sign your full name in this box: PRINT: _ (LAST) (FIRST) (MIDDLE) SIGN: TITLE CODE Copy this code in box on your answer sheet Then fill in the corresponding ovals exactly as shown Copy the Test Name and Form Code in box on your answer sheet 0 0 0 1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 9 9 Computer Science TEST NAME _ GR0329 FORM CODE _ GRADUATE RECORD EXAMINATIONS SUBJECT TEST B The Subject Tests are intended to measure your achievement in a specialized field of study Most of the questions are concerned with subject matter that is probably familiar to you, but some of the questions may refer to areas that you have not studied Your score will be determined by subtracting one-fourth the number of incorrect answers from the number of correct answers Questions for which you mark no answer or more than one answer are not counted in scoring If you have some knowledge of a question and are able to rule out one or more of the answer choices as incorrect, your chances of selecting the correct answer are improved, and answering such questions will likely improve your score It is unlikely that pure guessing will raise your score; it may lower your score You are advised to use your time effectively and to work as rapidly as you can without losing accuracy Do not spend too much time on questions that are too difficult for you Go on to the other questions and come back to the difficult ones later if you can YOU MUST INDICATE ALL YOUR ANSWERS ON THE SEPARATE ANSWER SHEET No credit will be given for anything written in this examination book, but you may write in the book as much as you wish to work out your answers After you have decided on your response to a question, fill in the corresponding oval on the answer sheet BE SURE THAT EACH MARK IS DARK AND COMPLETELY FILLS THE OVAL Mark only one answer to each question No credit will be given for multiple answers Erase all stray marks If you change an answer, be sure that all previous marks are erased completely Incomplete erasures may be read as intended answers Do not be concerned that the answer sheet provides spaces for more answers than there are questions in the test Example: Sample Answer What city is the capital of France? (A) (B) (C) (D) (E) A Rome Paris London Cairo Oslo B C D E A B C D E A B C D E A B C D E A B C D CORRECT ANSWER PROPERLY MARKED E IMPROPER MARKS DO NOT OPEN YOUR TEST BOOK UNTIL YOU ARE TOLD TO DO SO ® Educational Testing Service Princeton, New Jersey 08541 46 Scoring Your Subject Test Computer Science Test scores typically range from 540 to 860 The range for different editions of a given test may vary because different editions are not of precisely the same difficulty The differences in ranges among different editions of a given test, however, usually are small This should be taken into account, especially when comparing two very high scores In general, differences between scores at the 99th percentile should be ignored The score conversion table on page 49 shows the score range for this edition of the test only The worksheet on page 48 lists the correct answers to the questions Columns are provided for you to mark whether you chose the correct (C) answer or an incorrect (I) answer to each question Draw a line across any question you omitted, because it is not counted in the scoring At the bottom of the page, enter the total number correct and the total number incorrect Divide the total incorrect by and subtract the resulting number from the total correct This is the adjustment made for guessing Then round the result to the nearest whole number This will give you your raw total score Use the total score conversion table to find the scaled total score that corresponds to your raw total score Example: Suppose you chose the correct answers to 38 questions and incorrect answers to 22 Dividing 22 by yields 5.5 Subtracting 5.5 from 38 equals 32.5, which is rounded to 33 The raw score of 33 corresponds to a scaled score of 760 COMPUTER SCIENCE TEST PRACTICE BOOK 47 Worksheet for the Computer Science Test, Form GR0329 Only Answer Key and Percentages* of Examinees Answering Each Question Correctly QUESTION Number Answer P+ TOTAL C I QUESTION Number Answer P+ D C D C B 65 84 71 76 70 36 37 38 39 40 C A C A B 71 32 80 47 30 10 C ** ** A D 96 ** ** 41 78 41 42 43 44 45 D A C C C 47 66 65 48 18 11 12 13 14 15 A C C C B 68 46 76 60 69 46 47 48 49 50 C D C E C 56 33 56 60 26 16 17 18 19 20 D B C D C 42 48 77 71 42 51 52 53 54 55 C B E E D 36 43 33 37 71 21 22 23 24 25 A ** D D E 25 ** 41 70 72 56 57 58 59 60 A D B D E 27 68 39 38 24 26 27 28 29 30 A B A E ** 35 63 62 27 ** 61 62 63 64 65 A E C A E 53 36 52 45 18 31 32 33 34 35 E B A D D 45 42 55 34 49 66 67 68 69 70 E ** D D D 25 ** 40 35 23 Correct (C) Incorrect (I) Total Score: C – I/4 = Scaled Score (SS) = * The P+ column indicates the percent of COMPUTER SCIENCE Test examinees who answered each question correctly; it is based on a sample of November 2003 examinees selected to represent all COMPUTER SCIENCE Test examinees tested between July 1, 2000 and June 30, 2003 ** Items 7, 8, 22, 30, and 67 were not scored when this form of the test was originally administered 48 COMPUTER SCIENCE TEST PRACTICE BOOK TOTAL C I Score Conversions and Percents Below* For GRE Computer Science Test, Form GR0329 Only TOTAL SCORE Raw Score Scaled Score % Raw Score Scaled Score % 65 900 99 61-64 57-60 53-56 50-52 48-49 46-47 44-45 42-43 40-41 38-39 890 880 870 860 850 840 830 820 810 800 99 98 97 95 93 91 87 84 82 78 23 22 21 20 19 17-18 16 15 14 13 690 680 670 660 650 640 630 620 610 600 37 34 31 28 25 22 20 18 16 14 37 35-36 34 32-33 31 29-30 28 27 26 24-25 790 780 770 760 750 740 730 720 710 700 74 71 67 63 58 55 51 47 44 41 12 11 10 2-3 590 580 570 560 550 540 53 520 510 500 12 10 3 490 480 1 * Percent scoring below the scaled score is based on the performance of 10,579 examinees who took the COMPUTER SCIENCE Test between July 1, 2000 and June 30, 2003 COMPUTER SCIENCE TEST PRACTICE BOOK 49 Evaluating Your Performance Now that you have scored your test, you may wish to compare your performance with the performance of others who took this test Both the worksheet on page 48 and the table on page 49 use performance data from GRE Computer Science Test examinees The data in the worksheet on page 48 are based on the performance of a sample of the examinees who took this test in November 2003 This sample was selected to represent the total population of GRE Computer Science Test examinees tested between July 1, 2000 and June 30, 2003 The numbers in the column labeled “P+” on the worksheet indicate the percentages of examinees in this sample who answered each question correctly You may use these numbers as a guide for evaluating your performance on each test question The table on page 49 contains, for each scaled score, the percentage of examinees tested between July 1, 2000 and June 30, 2003 who received lower scores Interpretive data based on the scores earned by examinees tested in this three-year period will be used by admissions officers in the 2004-05 testing year These percentages appear in the score conversion table in a 50 column to the right of the scaled scores For example, in the percentage column opposite the scaled score of 730 is the number 51 This means that 51 percent of the GRE Computer Science Test examinees tested between July 1, 2000 and June 30, 2003 scored lower than 730 To compare yourself with this population, look at the percentage next to the scaled score you earned on the practice test Note: due to changes in the test-taking population, the percentile rank data changes over time Percentile rank information is kept current on the GRE Web site and may be obtained by visiting the GRE Web at www.gre.org/codelst.html, or by contacting the GRE Program It is important to realize that the conditions under which you tested yourself were not exactly the same as those you will encounter at a test center It is impossible to predict how different test-taking conditions will affect test performance, and this is only one factor that may account for differences between your practice test scores and your actual test scores By comparing your performance on this practice test with the performance of other GRE Computer Science Test examinees, however, you will be able to determine your strengths and weaknesses and can then plan a program of study to prepare yourself for taking the GRE Computer Science Test under standard conditions COMPUTER SCIENCE TEST PRACTICE BOOK đ 54721-007623 ã U54E8 ã Printed in U.S.A 724474 ... the Subject Tests Content of the Computer Science Test Preparing for a Subject Test Test- Taking Strategies What Your Scores Mean Practice GRE Computer Science Test Scoring... difficult than the test editions illustrated in the table COMPUTER SCIENCE TEST PRACTICE BOOK Range of Raw Scores* Needed to Earn Selected Scaled Scores on Three Computer Science Test Editions That... answer sheet COMPUTER SCIENCE TEST PRACTICE BOOK FORM GR0329 29 GRADUATE RECORD EXAMINATIONS® COMPUTER SCIENCE TEST Do not break the seal until you are told to so The contents of this test are confidential