Explain the concepts of reliability, validity, and utility. Do you consider them to be important? Why?

In business and marketing researches, the key goal is to collect certain data and determine whether it is accurate, or reliable and valid. The concepts of reliability, validity, and utility are most commonly used as important elements and techniques which help with the development of measurement scales and instruments for various social, scientific, psychological, and marketing researches.
Reliability alludes to the consistency of a measurement. It determines whether or not measures are free from error and therefore capable of producing consistent results; more consistency means higher reliability. If an instrument has fewer and fewer changes and variations in the results of the repeatedly analyzed data, then it means that it is more reliable. Reliability can be assessed and evaluated in three ways: test-retest reliability (the process of measuring is repeated with the same instrument and the same subjects), internal consistency reliability (using the instrument to measure different subjects, items, and samples in each scale), and equivalence (in which reliability is tested by devolving another instrument and using it to measure the same subject and samples).
Validity is closely related to reliability. Once an instrument has been determined reliable, we need to see and establish whether or not it’s reliably and correctly measuring what it’s supposed to be measuring. This is basically the instrument’s validity. There are four ways to assess validity: free validity (the researchers determine whether an instrument is valid or not), content validity (the researchers try to see whether the instrument has evaluated all aspects of the measured content), predictive validity (researchers determine if a measurement can predict future actions), and construct validity (this is more theoretical than practical and determines if a measurement truly tests what it’s supposed to test and applies the results to the researchers’ theories). There are more ways to evaluate validity; however, these four are most commonly used when it comes to marketing and business researches.
Aside from determining the reliability and validity of an instrument or a measurement scale, we also need to determine whether or not that measurement can be used in actual researches and analyses; in other words, the researchers need to see whether that measurement is practical. This means that the researchers are examining the instrument’s utility.
All three techniques are very important, as they help researchers get accurate results and apply those results to their theories, thus enabling them to examine more subjects or objects and try to improve the quality of people’s lives. If the results are not reliable or valid, then the research itself holds no relevant meaning.