Finally, since items referred to contextual stimuli, which were presented in textual formats, reading ability can be regarded as another, shared demand of solving the items.
Sketch (yes, no): This feature includes both sketches contained in the item formulations, which have to be read, interpreted, and/or understood for correctly solving the items or sketches as part of the respondents' answers.
Alternatively, they might have thought that understanding of the literal meaning would suffice to solve the items.
The two categories in this dichotomy are (i) the set of items for which knowledge of some mathematical theorem is helpful for solving the item, and (ii) the set of items where it is not.
For an item to fall into the T category, one of the following two criteria must be met: Either the item is designed in such a way that some theorem presumably known to the student significantly simplifies the task of solving the item, or the item is such that one would expect use of some theorem from the student.
For these analyses of differences in differences, it is convenient to have the results directly expressed as a difference in p-values, that is, in the percentages of tested students solving the item correctly.
While these different strategies did not impact problem-solving success (both groups solved the same number of items correctly), gesturing biased students toward considering more spatial aspects of the problem.
The items of the MDI comprise memory, habituation, problem solving, first number concepts, generalization, classification, vocalizations, language, and social skills (Bayley 1993).
As expected, the probability of solving the anchor items correctly increased from WBBt1 to WBBt2 by 19 percentage points on average, whereas the increase from WBBt2 to WBBt3 was about eight percentage points on average.
Thus, a basic model of test-taking motivation and engagement should include the "expectancy" of solving the test item as well as the "value" that the test-taker attaches to solving the test item (see Fig. 1).
