Avionics News January 2012 - 61

in documenting training will read or re-read the articles referenced in the training examination. The exam is open book, or in this case, open magazine. Not only can an examination initiate behavior, such as reading or studying, it also can modify behavior in other ways. Quizzes, basically a short test, can help a student focus on the important material. Students can be bombarded with information from a variety of sources. A short quiz can help the student determine the material to internalize and the material to leave in a notebook for future reference. In cases where attendance or tardiness is a problem, I’ll give an attendance quiz. This can take various forms, but in most cases, they are quite easy. The students present are rewarded with a good grade, and those who are absent are penalized with no grade. Any test or quiz must have validity and reliability. Throughout the years, I’ve seen tests which are both, one of the above or neither of the above. In general, if a test is valid, then it measures what it is designed to measure. For example, if I want to measure the ability of a student to recall modulation used by aviation VHF communication systems, then I could ask a simple question: What mode of modulation is used by aviation VHF communications systems? If I want to measure the ability of a student to test an aviation VHF communication radio, then the question above would not be valid. If one wants to measure the ability of a person to test a VHF comm, then the question above would only be one part of a larger test, perhaps a practical demonstration. In time, many have debated the validity of the Federal Communications Commission general radiotelephone operator test. The general belief the FCC test is not valid led to the development of the NCATT AET and its endorsements. A reliable test is a consistent test. In other words, it

consistently measures what it is supposed to measure. For example, a technician measures the voltage on a battery and gets a reading of 12.6 volts. If he or she stops to take a sip of coffee, then measures the voltage again, a consistent meter would read 12.6 volts again. If the meter read 50 volts the second time, then it would be considered unreliable. A reliable test will measure knowledge in a consistent way. I have experienced tests which were unreliable even though they demonstrated validity. In one case, the test was designed to measure a student’s skill at using a computer. The test was unquestionably valid. Those taking the test were evaluated in other ways, and the evidence clearly showed those who passed the test were able to use computers. The problem with this particular computer test involved reliability. There were a significant number of students who were skilled at using computers but could not earn a passing grade on the test. The examination was proving to be unreliable as a measure of computer use skill. A third function of a test could be to provide entertainment. Periodicals are full of questions designed to test your knowledge and entertain you at the same time. I enjoy the looks I get and the laughs I hear as my students reach the end of their final exam. After many difficult questions, I think they deserve a stress reliever. So, I include a question 51, or perhaps a question 101 (it depends on the test). The final question takes the form of a joke. Sometimes, the stem of the question is quite serious, while the answers are quite ridiculous. Other times, even the stem of the question causes the student to snicker. A little light entertainment is good for the soul. Alas, avionics boxes have no sense of humor. Fortunately, factory engineers have developed test procedures which are both valid and reliable. If the radio scores 100 percent, then we can be confident it’s airworthy. q
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2012

Avionics News January 2012

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