The Effect of Online Homework (IXL) on Students' Mathematics Achievement

We examined the potential different effectiveness of an online homework system (IXL) and the traditional paper-and-pencil homework. A study involving 98 participants was conducted in a middle school (grade 8). We compared the post-test results from the online homework group with the traditional homework group. Both homework assignment effect (class-level) and homework completion effect (student-level) proposed by Trautwein (2007) were investigated. No significant difference was found among the students who were assigned different types of homework (class-level). We conclude that IXL is as effective as the traditional homework on students' learning. Meanwhile, not surprisingly, we revealed that students who complete the homework outperformed the students who did not (student-level). We suggest that teachers give students an option to do online or traditional homework based on their preference, as long as they complete the homework.

Joint Matrix Decomposition-Based Missing Data Completion in Low-Voltage Area

In-depth mining and analysis of electricity data in low-voltage area are essential for the further intelligent development of power grids. However, in the actual data collection and measurement of low-voltage area, there will be missing data, and complete electricity data cannot be obtained. To obtain complete power data, this paper proposes a low-voltage station area missing data complement model based on joint matrix decomposition. First, we analyse the characteristics of the low-pressure station data. Then, a model that comprehensively considers the characteristics of the low-voltage station area data is proposed, which includes three parts: the construction of a low-voltage station area data tensor, the joint matrix decomposition, and the completion of the missing data, and it is named LPZ. After that, the CIM learning algorithm proposed in this paper is used to iteratively solve the model to obtain the completed data. Finally, the method proposed in this paper is used to complement the two situations of random loss and all-day loss of real current data in a low-voltage station area and compared with the traditional complement method. The experimental results show that this method is not only effective but also that the completion effect is better than that of other completion methods.

Does Broad-Based Merit Aid Improve College Completion? Evidence from New Mexico's Lottery Scholarship

We use the natural experiment of a state lottery scholarship to measure the effect of generous financial aid on graduation rates at New Mexico's flagship public university. During the study period, the scholarship program paid full tuition for eight semesters for any state resident earning a 2.5 grade point average in their first semester at any public two-year or four-year college. We find a significant positive completion effect of 10 percentage points (17.9 percent) for academically well-prepared students that is offset by a large negative effect of 11.6 percentage points (38.8 percent) for less-prepared students. We posit that the scholarship program, which effectively erased the difference in tuition at two- and four-year colleges, may have induced weaker students to take their chances on a more prestigious, yet riskier, academic path.