Standardized tests

Standardized testing is any test that is used across a variety of schools or other situations. Designers of such tests must specify a discrete correct answer for every question. This type of test includes both achievement (which measures knowledge already known) and aptitude (which attempts to predict future performance or potental) tests given to grade-school students, the English GCSEs, and the American SATs.

Standardized tests generally include at least some multiple-choice and true-false questions. These can be graded by computer, or by humans who do not understand the material in depth, as long as they have a list of the correct answers. One potential defect in such tests is that the test-taker can accidentally skip a line and then be marked wrong on material to which he or she knew the correct answer.

Standardized tests often include written portions as well; these are graded by humans who use rubrics, or guidelines, as to what a good essay on the subject will be.

Some believe that standardized tests make it possible to compare the achievements of students from different schools, eliminating bias from grade inflation and the influence of schools' reputations on university admissions officers. Others contend that standardized tests reinforce bias in education because students whose families have access to enrichment opportunities do better on such tests than students from other parts of a society. Such tests, as objective as they try to be, are tools of culture and are rooted in whatever cultural or philosophical understanding gave them rise.

Standardized tests only generate useful information if each question generates a ratio of correct to incorrect answers. So if nearly all test-takers get an answer correct, the test question needs to be eliminated from the test. Similarly, if nearly all test-takers get a particular question incorrect, the test question needs to be eliminated. Standardized objective tests create some meaning by comparing correct responses to incorrect ones.

Most frequently, tests are administered to people of similar ages or grades at particular times in development. This practice allows researchers to study correct to incorrect response ratios for 3rd graders (for example) over time or from region to region. The wide array of test-takers in a particular group generates data to establish normative classification for a group. Those data can serve as a guide for what that particular test finds as a normative response for that test. For that reason, many standardized tests are also called "norm referenced."

Most standardized tests are achievement tests and therefore have little predictive value for students, teachers or schools. They only generate good data for narrow skill sets or topics. However, many school systems use standardized testing as a screening tool, as a basis for curriculum or as a broad comparison between students. Standardized tests have limited value and need to be regarded as only one way to measure performance, potential or intelligence.

Originally a standardized test was simply a standard test – of academic achievement or of knowledge in a specific academic or vocational domain. It has since acquired the meaning of a written test whose scores are interpreted by reference to the scores of a norm group which has taken the test and which is usually considered to be representative of the population which takes the test. For example, standardized tests of academic achievement provide conversion tables showing the percentile ranks in the norm group of all possible raw scores. Some standardized tests are now analyzed with item response theory.

History of standardized tests
Perhaps the earliest evidence of standardized testing based on merit comes from China during the Han dynasty (206 BC-202 AD). The concept of a state ruled by men of ability and virtue was an outgrowth of Confucian philosophy. The imperial examinations included the so-called Six Arts which included music, archery and horsemanship, arithmetic, writing and knowledge of the rituals and ceremonies of both public and private life. Later, the five studies were added to the testing (military strategies, civil law, revenue and taxation, agriculture and geography in addition to the Confucian Classics).

Criticisms of standardized tests
Standardized tests are widely used in education, placement and certification. Their validity has been criticized on several grounds.

Some of the criticisms are standard psychometric ones. For example, scores on tests of achievement in mathematics problem-solving are often correlated with scores on tests of language ability; this suggests that the mathematics test is actually measuring the linguistic ability required to understand the presentation of the problems rather than the mathematical ability required to solve them. Educational tests also tend to become outdated as curriculum changes.

Standardized tests are also widely criticized as culturally inappropriate for many groups, both in content and in process. Criticism of content usually centers on the differing relevance of the content to people from different cultures – for example, newly arrived immigrants can be expected to have greater difficulty with an intelligence test which asks them to name past leaders of the country to which they have recently immigrated.

Attempts have been made to develop culture-free and culture-fair (culture-neutral) tests of intelligence, but on the whole these attempts have not been successful. Conceptions of intelligence vary widely from culture to culture, and abstracting the few common elements, or what appear to be the few common elements, cannot be depended on to produce a reliable guide to intelligence.

A common criticism of standardized testing programs in schools is that they encourage teachers to "teach to the test." That is, teachers concentrate on the parts of the curriculum they know will be covered on the test and neglect those that will not. This criticism is certainly worth considering if teachers have foreknowledge of the test and the test is not comprehensive. However, if enough alternative forms of the test are provided, if teachers do not know which form will be used, and if the forms provide a comprehensive sampling of the curriculum, this danger would probably be avoided. Despite the obvious danger of teaching to the test in certain circumstances, though, little research has investigated the prevalence of the phenomenon, or its effects. Furthermore, any form of testing will promote teaching to the test if the consequences of testing are serious and the material on the test is known beforehand.

A related criticism is that students whose teachers train them in test-taking skills unrelated to content will perform better than equally accomplished students whose teachers do not. Some simple test-taking skills can improve scores on multiple-choice standardized tests, so this criticism points to a real danger, especially if standardized tests are used (incorrectly) as the sole measures of achievement or skill. However, little research has investigated the prevalence or effects of this training.

Standardized tests are also criticized for emphasizing recall and recognition rather than higher-order cognitive skills. However, this criticism is not generally valid. While many standardized tests do emphasize recall and recognition, many others assess analytical skills.

Another criticism is that standardized tests assess inadequate samples of skills. Again, however, this criticism cannot validly be made of all standardized tests, although it can be made about the majority of tests of any type.

Not without importance is the correlation between standardized test performance and social class and/or degree of wealth. Those who can afford to take often expensive secondary test prep courses designed especially to teach one how to take the test can enjoy a huge advantage over those who cannot afford such courses, which reflects resources available to the student, and not necessarily academic merit.

Large-scale attempts have been made to substitute performance assessment or "authentic" testing for standardized academic testing. Performance tests require actual performance of a skill; for example, instead of answering questions about a science experiment, a student would be required to perform it. However, performance tests have poor reliability simply because they accumulate so little data. Standardized tests have been found to predict scores on performance tests better than other performance tests do.

Much of the opposition to standardized tests has centred on the incorrect use of these tests. In particular, the use of standardized tests of academic achievement to assess individual students is questionable, given the tests' reliability – they are simply not accurate enough to provide adequate assessments of individual students by themselves.

Perhaps the most important criticism of standardized testing is that many standardized tests fail to meet the standards of their own field. For example, tests of adult literacy are widely used, although there is little evidence that they assess literacy accurately.

In Britain the political impact of standarized testing in recent years has been that it has been used to criticise the performance of individual schools and the teaching profession. It is bound up with national, centralised, inspection and appraisal.

Advantages of standardized tests
Perhaps the simplest advantage of standardized tests is that they are standardized. While some people may systematically score lower on certain tests, these differences will be systematic. On the opposite end of the spectrum, scores on subjective tests change significantly according to whoever is grading them. In the case of college admissions, for example, interviews with prospective students has been repeatedly shown to predict later college performance no better than chance, while statistical measures such as prior GPA or SAT scores are much more accurate.

One of the main advantages of standardized testing is that it is able to provide assessments that are psychometrically valid and reliable, as well as results which are generalizable and replicable.

Another advantage is aggregation. A well designed standardized test provides an assessment of an individual's mastery of a domain of knowledge or skill which at some level of aggregation will provide useful information. That is, while individual assessments may not be accurate enough for practical purposes, the mean scores of classes, schools, branches of a company, or other groups may well provide useful information because of the reduction of error accomplished by increasing the sample size.

While standardized tests are often criticized as unfair, the psychometric standards applied in the development of standardized tests would produce fairer testing if applied in other types of testing. In particular, the effectiveness of each test item in accomplishing the goal of the test would have to be demonstrated.