Introduction
Psychologists use different instruments to measure variables. The selection of the test instruments depends on the variable that is intended to be measured (Cohen, 2002). The instruments used for psychological assessment are not perfect. Therefore, in choosing the tool, the psychologists have to consider the error that is acceptable concerning the tool (Luce & Kahn, 2000). The prediction of behaviour for adolescents is a useful variable that can be assessed in the admission of adolescents to counselling programs. According to Cattell and Mead (2008), the wider scope of the prediction of adolescent behaviour is based on the measure of the personality.
The 16PF Adolescent Personality Questionnaire
The most relevant tool to measure the personality variable for adolescents is the 16PF Adolescent Personality Questionnaire. 16PF Adolescent Personality Questionnaire is an instrument commonly applied to assess normal personality range of adolescents (Cattell & Mead, 2008). The instrument is designed to measure the structural elements of personality. The 16PF Adolescent Personality Questionnaire is a multi-level instrument. The different levels of the tool are integrated to provide an in-depth evaluation, and prediction of the accurate behaviour of the individual being tested (Cattell & Mead, 2008). The 16 PF Adolescent Personality Questionnaire identifies personal dimension that is problematic for adolescents (Cattell, 2003). The instrument is not limited to normal range personality of the adolescents; the ability to identify the problematic areas in adolescents makes it applicable in counselling.
The 16PF Adolescent Personality Questionnaire is very useful in the prediction of behaviours (Cattell & Mead, 2008). Psychologists use it to understand important information. However, the assessment of the different variables is not perfect. Important factors that should be considered in the application of any measurement instrument include the rates of hits, misses, false positives, and false-negative errors.
Hits
Hit rate refers to the percentage expression of cases, in which a test instrument predicts as a failure or a success (Cohen, 2002). A hit rate is a rate an instrument can accurately identify a given trait or attribute. For example, in the application of the 16PF, hit rate entails the accuracy of the test instrument in reproducing the attributes that affect the personality of the adolescents.
Misses
Misses are the percentage of the test subjects that the test instrument does not accurately identify. Misses are categorized into false positives and false negatives (Cohen, 2002). The failure to identify a trait implies false classification or prediction of some attributes.
False-positive
False-positive refers to a prediction of personality that is inaccurate. It implies that the person being tested has a given trait or attribute that is being assessed but in reality, the attribute is not possessed by the individual (Cohen, 2002). For example, in measuring the ability of the adolescent, the test may point to the adolescent having a given attribute; however, in actual practice, the adolescent may not complete tasks that relate to the ability.
False Negative
False-negative refers to a miss rate in which the prediction of an attribute is inaccurate. It implies that the individual being tested does not possess an attribute; however, in reality, the individual has the trait (Cohen, 2002). For example, in a general test, an adolescent can test negative for the consumption of a drug, but in reality, the adolescent has been using the drug.
Relevance to Interpreting Constructs
The interpretations of test results have different implications for the outcomes. In the analysis of constructs, the point to the accuracy of the instrument is hit. As a result, in the measurement of a construct, the hits of 16PF Adolescent Questionnaire point to the reliability of the instrument to denote the right attribute measured (Cattell, 2003). According to Cattell and Mead (2008), the personality of an adolescent is based on a stable behaviour that relates to cognition of the individual. In the interpretation of the construct, the hit rates come to play in the provision of the normal personality information beyond what is known to the individual. Therefore, the effect of the hit rate is a pointer that the variable being measured is correctly identified.
Misses are either false positives or false negatives. The consequence of the construct being measured is that misses lead to an outcome that has a negative consequence (Luce & Kahn, 2000). A test with misses signifies errors, which have a negative implication on the outcome. For instance, a miss in the prediction of the personality of an adolescent may have high-cost implication such as the failure to achieve a targeted goal. In selection for admittance in a counselling program, a miss may have a great implication on the future of the adolescent. Luce and Kahn (2000) noted that a false positive and a false negative influence the decisions that are made concerning the test taker. According to Cattell (2003), if a test fails to detect a malady, it implies that the problem is not solved, or a solution is designed for an absent problem.
Cattell and Mead (2008) noted that psychological measurement instruments are to err. The errors have grave implications. A miss, either positive or negative. is undesirable. The implication of not identifying an attribute is normally greater than the implication of overprescribing an attribute. Therefore, test instruments are designed to ensure that they err on the false positive rather than on the false negative. The interpretation of results from the 16PF Adolescent Personality Questionnaire that predicts false-positive implies that many adolescents are identified as having the problem being measured. The implication for a false negative is that important attributes or predictions are missed; hence, the overall outcome is undesirable. For example, adolescents with attributes associated with a problem are not positively identified.
Relevance to Validity
The validity of the test entails the degree, in which the test or test instrument achieves what it is designed to measure (Cohen, 2003). According to Cohen and Mead (2008), validity refers to the judgment that a tool measures what it is designed to measure. The validity of measurement is significant in ensuring that inferences drawn from the test are appropriate. A valid test implies that the generalizations and inferences made from the measurement are accurate and appropriate for the expected use. For instance, the 16PF Adolescent Personality Questionnaire is valid if it accurately predicts the personality of an adolescent.
The hits, misses, false positive and false negatives are significant in the determination of the degree of validity of the test instrument. The four issues affect the internal consistency of the instrument and hence are crucial in determining the ability of the instrument to measure what it is intended to measure. A high hit rate of a 16PF Adolescent Personality Questionnaire points to increased validity of the instrument. It implies that the instrument produces reliable results. The 16PF Adolescent Personality Questionnaire has been found to have high hits in the prediction of the personality structure (Cattell, 2003). The application of the instrument across cultures yields high scores in peer rating and minimizes bias. The high hits point to the reliability of the instrument in the production of accurate results. The relevance of the high hit rate implies that the instrument can be applied to the measuring of the cognitive psychology of adolescents. An example is an application in the personality study of adolescents’ social inclinations, attributes, and perceptions.
An instrument that does not achieve accurate results signifies that it is reliable for validity (Cattell & Mead, 2008). Misses, which result in false positive or false negative compromises the validity of the test instrument and thus the instrument, are not reliable. A high miss rate in a test instrument shows that the test instrument does not give the desired outcome. A high miss rate reduces the validity of the instrument used for measurement.
Conclusion
In conclusion, the 16PF Adolescent Personality Questionnaire provides a comprehensive basis for assessing the personality of adolescents. It is applicable in determining the personal attributes of adolescents. Due to its comprehensiveness, the 16PF Adolescent Personality Questionnaire has a high hit rate that points to the reliability and validity of the instrument. However, just like the other psychological measuring instruments, there are possibilities of misses, which result in false positives or false negatives. The design of the 16PF ensures that it has high hits and in case of errors, the design is skewed in the false positive. The design increases the validity and minimizes the negative implication of the false negatives.
References
Cattell, H. (2003). Essentials of the 16PF Assessment. New York, NY: John Wiley & Sons.
Cattell, H. and Mead, A. (2008). The Sixteen-Personality Factor Questionnaire (16PF). London: Sage Publishers.
Cohen, R. (2002). Psychological Testing and Assessment: An Introduction to Tests and Measurement. London: McGraw-Hill.
Luce, M. and Kahn, B. (2000). The Psychology of False‐Positive Test Results. Journal of Consumer Research, 26(3), 242-259.