Previous studies have identified physics students' difficulties with graph slope and area under a graph in different contexts. In this study we compared physics and nonphysics (psychology) students' understanding of graphs; i.e., we evaluated the effects of concept (graph slope vs area under graph), type of question (qualitative vs quantitative), and context (physics vs finance) on their scores, strategies, and eye-tracking data. All students solved questions about graph slope better than the questions about area under a graph. Psychology students scored rather low on the questions about area under a graph, and physics students spent more time on questions about area under a graph than on slope questions, indicating that understanding of area under a graph is quite a difficult concept that seems unlikely to develop spontaneously. Generally, physics students had comparable scores on the qualitative and quantitative questions, whereas psychology students solved qualitative questions much better. As expected, students' scores and eye-tracking measures indicated that problems involving physics context were easier for physics students since they typically had higher scores and shorter total and axes viewing times for physics than finance questions. Some physics students may have transferred the concepts and techniques from physics to finance because they typically scored better than psychology students on the finance questions that were novel for both groups. Analysis of student strategies showed that physics students mostly relied on strategies learned in physics courses, with strong emphasis on the use of formulas, whereas psychology students mostly used common-sense strategies, as they did not know the physics formulas. The implications of the results for teaching and learning about graphs in physics courses are also discussed.

This study proposes a new methodology for determining the relationship between child-directed speech and child speech in early acquisition. It illustrates the use of this methodology in investigating the relationship between the morphological richness of child-directed speech and the speed of morphological development in child speech. Both variables are defined in terms of mean size of paradigm (MSP) and estimated in a set of longitudinal spontaneous speech corpora of nine children and their caretakers. The children are aged 1;3–3;0, acquiring nine different languages that vary in terms of morphological richness. The main result is that the degree of morphological richness in child-directed speech is positively related to the speed of development of noun and verb paradigms in child speech.

No abstract

Developing a better understanding of the measurement process and measurement uncertainty is one of the main goals of university physics laboratory courses. This study investigated the influence of graphical representation of data on student understanding and interpreting of measurement results. A sample of 101 undergraduate students (48 first year students and 53 third and fifth year students) from the Department of Physics, University of Zagreb were tested with a paper-and-pencil test consisting of eight multiple-choice test items about measurement uncertainties. One version of the test items included graphical representations of the measurement data. About half of the students solved that version of the test while the remaining students solved the same test without graphical representations. The results have shown that the students who had the graphical representation of data scored higher than their colleagues without graphical representation. In the second part of the study, measurements of eye movements were carried out on a sample of thirty undergraduate students from the Department of Physics, University of Zagreb while students were solving the same test on a computer screen. The results revealed that students who had the graphical representation of data spent considerably less time viewing the numerical data than the other group of students. These results indicate that graphical representation may be beneficial for data processing and data comparison. Graphical representation helps with visualization of data and therefore reduces the cognitive load on students while performing measurement data analysis, so students should be encouraged to use it.

No abstract