Reliability and Validility
Reliability and Validity Ebony Johnson University of Phoenix Reliability has to do with the quality of measurement and is the consistency of repeatability of measures. To define it precisely researchers first have to learn about the foundation of reliability- the true score theory of measurement. Then researchers need to understand the different types of measurement error because they play a key role in degrading reliability. Because reliability can only be estimated there are different types of reliability that has multiple ways to estimate reliability for that type.
In the end it is important to integrate the idea of reliability with the other major criteria for the quality of measurement, validity. Validity refers to the degree to which a study accurately reflects or assesses the specific concept the researcher is attempting to measure. Validity is concerned with the study’s success at measuring what the researchers set out to measure. Reliability is defined as a criterion used to define the consistency, stability, and dependability of how all the information is suited for the purpose intended.
For example, when researchers look at human services and human service management reliability can be used to measure the behaviors associated with parenting skills, job performance or mental health status. There are five types of reliability alternate form reliability is the degree of relatedness of different forms of the same test. Then there is internal-consistency reliability, which is the degree of relatedness of items in a test or all raters in a judgment study. Judge-to-judge reliability is the reliability of any single item on average.
Finally, test-retest reliability which is the degree of temporal stability of a measuring instrument or test, or the characteristic it is designed to evaluate from one administration to another. Validity is a measure used to show how well the measure or design does what it states that it is going to do. For example, when it comes to human services validity can be tested by a psychological test. The test would be used to measure one’s cognitive ability or to test one’s ability function independently. Validity is how accurate was the guess or the assumption made.
An example would be if schools mandated a stricter attendance policy, did class participation increase or decrease? There is several types of validity the ones that are useful in human services management is conclusion, internal, construct, content and external validity. Construct validity is there a connection between attendance and class participation? Internal validity is did the attendance policy cause the participation to increase? Construct validity is the degree to which the conceptualization of what is measured or experimentally manipulated is what it claims to be.
Content validity is the adequate sampling of the relevant material or content that a test claims to measure. External validity is can researchers take the results of our study of the attendance and class participation to another classroom or school and obtain similar results Data collection methods The degree of reliability and validity for data collection methods and instruments are important to establish the value of research information. According to Rosnow ; Rosenthal (2008), validity “shows how well the measures or the design does what it purports to do” (p. 124).
Reliability is the consistency or stability of the measures of the data collection methods and may imply dependability (Rosnow ; Rosenthal, 2008). The reliability and validity of the data collection provides a basis for correlation, relatedness, and replication of the research. Well-grounded research provides an explanation of the data collection methods with the degree of reliability and validity plus the measures for a margin of error. Reference Rosnow, R. L. , ; Rosenthal, R. (2008). Beginning behavioral research: A conceptual primer (6th ed. ). Retrieved from The University of Phoenix eBook Collection database.
