Intlligence Defnition and Measure Essay

Intlligence Defnition and Measure Essay.

Defining and measuring intelligence remains just as controversial as it was when the first very first intelligence test was developed and administered. Over the years, various instruments have been developed, but intelligence ultimately remains undefined. In this paper, the writer will critique the major definitions of intelligence and determine the most appropriate definition for each intelligence and achievement instrument. The writer will consider the ethical implications of utilizing intelligence and achievement tests in educational settings. Lastly, the writer will compare and contrast the selected achievement and intelligence measurements.

Intelligence Definitions

The Merriam -Webster online dictionary defines intelligence as: (1). the ability to learn or understand to deal with new trying situations, (2). the ability to apply knowledge to manipulate one’s environment or to think abstractly as measured by objective criteria (tests). Cohen and Swerdlik (2010), notes that intelligence manifest itself in the following abilities: acquiring and using knowledge, logically reasoning skills, effective planning, perception, judgment making, problem solving attention, visualizing concepts, intuition, and coping, adjusting, and dealing with situations.

However, theses abilities do not absolutely define intelligence, instead, they provide an outline of characteristics in which intelligence can be measured.

Francis Galton, Alfred Binet, David Wechsler, and Jean Piaget are considered the most influential contributors in developing, defining and understanding intelligence. Galton is known for making the first serious attempt to develop measures which would assess a person’s intelligence. Galton proposed the intelligence was merely a combination of the right genes. He believed that there was a correlation between intelligence and physical development of the brain and body.

Wechsler defined intelligence as “the aggregated or global capacity of the individual to act purposefully, to think rationally and to deal effectively with his environment” (Cohen & Swerdlik, 2010, p. 280). He further reasoned that each that no two individuals share the same intelligence, thus, intellectual abilities should be uniquely measured. Unlike the others, Piaget does not actually define or explain what intelligence is; rather he explains how it is developed (Cohen & Swerdlik, 2010). Piaget proposed that intelligence starts developing in early childhood. He believed during this stage, children learned essential cognitive skills to assist in adaptation. Binet developed an important intelligence measure known as the Stanford-Binet Intelligence Scales. However, he did not define intelligence. Instead, he outlined components of intelligence, such as “reasoning, judgment, memory and abstraction.” (Cohen & Swerdlik, 2010, p. 280).

Intelligence and Achievement Measures

The two intelligence measures selected for evaluation are the Standford-Binet Intelligence Scales – Fifth Edition and Wechsler Adult Intelligence Scale – Fourth Edition. The Standford-Binet Intelligence Scale, fifth Edition is also referred to as the SB5. There have been various editions over the years, but this assessment has undeniably become known as the standard for intelligence measurement. The assessment was originally developed by Alfred Binet and Theodore Simon. The SB5 is considered an assessment for all ages. The test comprehensively measures five factors of cognitive ability: (1) fluid reasoning, (2) knowledge, (3) quantitative processing, (4) visual-spatial processing, and (5) working memory.

The Wechsler Adult Intelligence Scale – Fourth Edition is also referred to as the WAIS. The test is designed to measure intelligence of individuals between 16-90 years old. The most recent version of the test is composed of 10 core subtest and five supplemental subtests. Previous versions included the verbal/performance subscales, but those subscales have been replaced by the index scores in the WAIS-IV. The General Ability Index was included (GAI) which consists of the Similarities, Vocabulary and Information subtests from the Verbal Comprehension Index and the Block Design, Matrix Reasoning and Visual Puzzles subtests from the Perceptual Reasoning Index (Wikipedia The Free Encyclopedia, 2010).

The two achievement measures selected for evaluation are the Stanford Achievement Test, Tenth Edition and Wechsler Individual Achievement Test, Third Edition. The Wechsler Individual Achievement Test is an extension of his definition of intelligence. The test is composed of 16 subtests and was developed with the intent to assess each person’s intelligence differently. The Standford achievement test is also referred to as the SAT. This test is administered to high school students. The test assesses developed reasoning. It was initially devised as an instrument to identify gifted students from underprivileged backgrounds. It was presumed to measures aptitude rather than knowledge students acquired through school.

Reliability, Validity, Normative Procedures, and Bias

Reliabilities for the WAIS are considered to be “very good.” Additionally, the Standard Error of Measurement (SEM) is commonly small. The subtests have test-retest reliabilities between .81 to .94, with a few falling lower. As to practice effects over a one to three month time, Verbal IQ increased about 3 points, Performance IQ about 6 to 7 points, and Full Scale IQ about 4 or 5 points. Inter-rater reliability is also rather good (Niolon, 2005).

According to Niolon, content validity is determined by expert judges who review the items (2005). Criterion Validity was determined by correlating WAIS-R and WAIS III. The WAIS III is also correlated with other measures to include the: SB4, the WISC-III, and the WIAT. Construct validity was established through factor analysis. Studies found that g was supported, and that verbal subtests correlated better with each other than performance subtests. The same was true for performance subtests verses verbal, but not as strongly (Niolon, 2005). The normative procedures consisted of a sample size of 2200 participants. There were 200 examinees per age band for ages 16-69 and 100 examinees per age band for ages 70-90. The national sample was stratified by: sex, education level, ethnicity and region (Pearson, 2008).

The Standford-Binet Intelligence Scales were measured for reliability using the interscorer agreement, the split-half method, and the test-retest method. Normative data for the SB5 was collected from 4,800 individuals between the ages of 2.0 and 85 + years. According to Roid, the normative sample closely matches the 2000 U.S. Census (2003). Bias reviews were conducted on all items by considering the following variables: ethnicity, cultural, region, religion, gender, and socio-economic status. This test was co-normed with the Bender-Gestalt Visual-Motor Gestalt Test, 2nd Edition. Reliabilities for the test have been reported as “very high.” Reliabilities notably range from .95 to .98 (average internal consistency composite reliability, across all age groups) (Roid, 2003). For the factor indexes, reliability range from .90 to .92. The ten subtests have consistently measured between .84 to .89 for reliability However, concurrent and criterion validity data is established by using other measures such as Stanford-Binet Form L-M, Woodcock-Johnson III, WAIS III etc.

Compare and Contrast Intelligence and Achievement Assessments Goals

The primary objective of the WAIS IV is to demonstrate updated foundations, improve the developmental appropriateness, make the test more accessible by approving user friendliness, increase developmental appropriateness, boost clinical use, and improve psychometric features (Wechsler, 2008). The primary goal of the Standford-Binet Intelligence Scales, Fifth Edition is to be a valid and comprehensive assessment tool of which measures intelligence and cognitive abilities (Roid, 2003).

The objective of the SAT, Tenth Edition is to assess academic progress and to indentify those with special needs. Finally, the main goal of the Wechsler Individual Achievement Test, Third Edition is to “provide more in-depth academic assessment and intervention recommendations particularly for students who may have specific learning disabilities” (Pearson, 2009, para.

1). Uses

The Wechsler Intelligence Scales should be administered by trained professionals within a 90 minute time frame. The test has many versions which assess children, adolescents, and adults. There are several subscales, but the verbal scales specifically measure: general knowledge, memory, language, and reading. The performance scales assess spatial reasoning, problem solving and sequencing (IUPUI, 2011). The Standford-Binet Intelligence Scales assess verbal and nonverbal abilities. The assessment generally administered between 15 to 45 minutes considering which areas are measured (Roid, 2003).

The SAT is an educational assessment usually administered by pencil and paper. This assessment is untimed and facilitators do not require specialized training. The Wechsler Individual Achievement Tests has been revised to accommodate individuals between 4-50 years old. The test can last as long as two hours and is administered by pencil and paper.


The Wechsler Intelligence Scales are used for the following purposes: identifying learning disabilities, determining suitability for school placement, identifying intellectual giftedness, and assessing intellectual development. According to Roid, The Standford-Binet Intelligence Scales are used for clinical assessment, neuropsychological assessment, early childhood assessment, placement in special education classes, career assessment, and indentifying developmental delays (2003).

The purpose of the SAT is to measure educational progress in individuals ages 5 to 19. They are tested on their ability to learn and retain course materials, and to determine if they meet criteria for special education, honors, or remedial courses. Finally, the purpose of the Wechsler Individual Achievement Test is to determine academic level of individuals and to determine if individuals have any specific learning qualities (Pearson, 2009).

Ethical Considerations in Education

As with any form of testing, there are certainly ethical implications with intelligence and achievement testing. Major concerns include: labeling, segregation based on scoring, and privacy violation. According to Denmark, standardized tests must effectively gauge student achievement without giving certain students an advantage over others. Some researchers suggest that the way the tests are composed causes a particular group to be more likely to misinterpret information due to cultural background, language/dialect inference and gender (2013). Other ethical issues include: gender bias, linguistic bias, test security and alternative assessment.


Intelligence and achievement tests come in many different forms. Test administrators are left with a tedious task of identifying which assessment best measures the populations needs. In addition, ethical elements must be considered. With all the assessments, there is still no one test which measures intelligence in its totality. The instruments do in fact help professionals identify giftedness or intellectual disability. As a result, individuals are afforded a better learning environment with specific tools designed to help them successfully meet their needs.

Cohen, R. J., & Swerdlik, M. E. (2010). Psychological testing and assessment: An introduction to tests and measurement (7th ed). New York, NY: McGraw-Hill. Denmark, Bonnie (2013). Ethical Issues in the Preparation of a Standardized Test. Retrieved from: on February 4, 2013. Merriam-Webb Online Dictionary. Retrieved from: on February 4, 2013. Niolon, Richard (2005). Introduction to the WAIS III. Retrieved from: on February 4. 2013. Pearson. (2009). Wechsler Individual Achievement test-Third Edition. Retrieved from Mental Measurements Yearbook.

Roid, G (2003). Stanford-Binet Intelligence Scales, Fifth Edition. Retrieved from Mental Measurements Yearbook.

Intlligence Defnition and Measure Essay