An alternative-response item is a special case of themultiple-choice item format. There are many situations which call for either-or decisions, such as deciding whether a specific solution is right or wrong, whether to continue or to stop, whether to use a singular or plural construction, and so on. For such situations, the alternative response item is an ideal measuring device. Since only two options are possible, alternative-response items are generally shorter, and, therefore, require less reading time. Students may respond to more alternative-response items than other types of items in a given length of time.
A major disadvantage of alternative-response items is the fact that students have fifty-fifty probability of answering the item correctly by chance alone. When carefully written and pretested, alternative-response items may be written which exceed multiple- choice items in ability to discriminate. Generally, however, it is considered necessary to have a larger number of alternative-choice items than of other types of items in order to achieve a given level of test reliability.
There are two main types of alternative-response items. One type is essentially a two-option multiple-choice item. An example follows.
To determine the degree of relationship between two continuous variables, one must compute the
- product-moment coefficient of correlation.
- rank-order coefficient of correlation.
A second type of alternative-response item is the complete statement format, the most familiar example of which is the true-false item.
To determine the degree of relationship between two continuous variables, one must compute the rank-order coefficient of correlation.
Ensure that True and False Items are Approximately Equal in Length Since we often have to qualify statements in order to make them unequivocally true, test-wise students often use item length as an extraneous clue. Efforts should be made to write false items of about the same length as true items.
Balance the Number of True Items and False Items The number of true and false items should be approximately balanced so that test-wise students will approach an item on the basis of its content rather than on the probability of its being true or false. Some authors argue that the proportion of false items should exceed the number of true items. They argue that, in general, respondents tend to agree with statements rather than disagree with them. Thus the false items will tend to be somewhat more difficult and the total test will be somewhat more reliable.
Eliminate Vague Terms of Degree or Amount Words like “frequently” and “seldom” are especially open to interpretation in true-false items, which have no built-in frame of reference. It is generally possible to edit such vague terms out of true-false items.