bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of the mean-absolute deviation portfolio investment in some mining stocks using the singular covariance matrix method
Authors: Kalfin  , Sukono  , Carnia E 
Published: October 2019

Abstract
Investing in mining stocks, investors often face risk problems. Usually to minimize risk, it is done by forming an investment portfolio. This paper aims to discuss the optimization of the investment portfolio. The data analyzed are several mining stocks traded on the capital market in Indonesia. Optimization is done using the mean-absolute deviation model with the singular covariance matrix method and the non-singular covariance matrix method to determine the optimal weight of the two existing methods. Based on the results of the optimization, we can obtain a weight allocation composition that provides an optimal portfolio. In addition, we also estimate the amount of return on expectations and risks in the optimal portfolio formed. So that the composition of this optimal weight can be used as a consideration for investors in investing their capital in several analyzed mining stocks.
Conceptualization in solving a geometric-function problem: an effective and efficient process
Authors: Alghadari F , Yuni Y , Wulandari A 
Published: October 2019

Abstract
There has been more than one the solving process of the problem sometimes. It has been named an open-ended context when related to an approach, and in this study, purposed to use a geometric-function problem for analyzing each process that was experienced a student when they were conceptualizing the completion. Three students purposively who was a sample is registered by the senior high school in a science program at the region of West Jakarta, Indonesia. Student solved the problem in this explorative study, there were two choices of completion ways, technical or conceptual, but they used the procedural technique operational. Two conceptualizing process in solving the problem, it was constructing the algebraic representation of the function and organizing concepts. But, there is only one between the other where was effective and efficient of the process based on the perspective of the management theory. The first process was efficient by recognizing the function in algebraic and graphic representation. But, the second process affected the solution ineffective because all three students have been miss controlling the domain function concept even though it is a resource. So, an effective and efficient for learning is when students involving more conceptual knowledge.
Student’s mathematics literacy skills in solving of PISA type problems financial context
Authors: Dayona Gold , Zulkardi  
Published: October 2019

Abstract
From outstanding issues, about UN questions in Indonesia adopted from the standard PISA/TIMSS. Skills in PISA questions can be used as a reference to knowing students’ mathematics literacy skills. The challenge as a researcher now is to present questions that can be used for students practicing questions similar to PISA questions. The purpose of this article is to know students’ mathematical literacy skills in solving PISA type math problems that researchers have developed. The research method in this article is a design research type of development study which consists of two stages, namely preliminary and formative evaluation. The preliminary stage consists of analysis and design. And the formative evaluation stage consists of self-evaluation, expert reviews, one-to-one, small groups, and field test. Students’ mathematical literacy skills can be seen from the results of the field test. The mathematical literacy skills seen is communication skill, mathematizing skill, representation, reasoning and arguments skill, and skill to use mathematical tools.
Logical thinking skills of prospective elementary school teachers
Authors: Ristiana M G 
Published: October 2019

AbstractA teacher should present a lesson concept well, not just only using it to solve a question on exams. However, the teacher should make their students understand all of the concepts. This thing should be built since we are in a golden age or elementary school. Elementary school teacher should have better skills in teaching, because they teach a lesson base, especially mathematics. If students do not understand the base of mathematics, they will not be able to solve more complex mathematics problems. Therefore, logical thinking skill is needed for this, especially for an elementary school teacher. This research aims to see whether students of prospective elementary school teacher have a good logical thinking skill or not. To do so, we used the descriptive qualitative method. We presented an easy mathematics questions to see their logical thinking skills. The result shows that prospective elementary school teacher students did not have good logical thinking skills yet. They still should increase their logical thinking skills to be a better teacher. Their lecturer should have a better teaching concept to make a better elementary school teacher later.
Effect of problem based learning with didactical engineering on student mathematical disposition
Authors: Miliyawati B , Herman T 
Published: October 2019

Abstract
The purpose of this study is to comprehensively describe the effect of problem based learning (PBL) with didactical engineering (DE) on students’ mathematical dispositions. The research method used was quasi-experimental, with the research design of Posttest-Only Design with Nonequivalent Groups. The population in this study were all eight grade students in one of the State Junior High Schools in Subang Regency and the samples involved were 43 students spread in two classes, namely the experimental class and the control class. The instruments used in this study were mathematical disposition scale questionnaires and guidelines for observing teacher and student activities. Data analysis was carried out quantitatively and the statistical test used was the t test, Mann-Whitney test, two-way ANOVA. Based on the results of data analysis it can be concluded that learning factors influence the mathematical disposition of students but based on the PMA category does not affect the mathematical disposition, and there is no interaction between the learning model and the PMA category.
The Effect of STAD cooperative model by GeoGebra assisted on increasing students’ geometry reasoning ability based on levels of mathematics learning motivation
Authors: Rahmat  , Fahinu  , Alfat Sayahdin , Maryanti Era 
Published: October 2019

Abstract
This study aims to analyze the improvement of geometric reasoning abilities of students of SMA Negeri 1 Sampara, Kabupaten Konawe, Sulawesi Tenggara, Indonesia. Here, we compare three models of learning; (1) STAD cooperative model by GeoGebra assisted; (2) a model of the STAD cooperative without assistance from GeoGebra; and (3) conventional learning models. This study was applied to three different classes, where each class consisted of the high, medium, and low motivation students. Data collection was done by giving a mathematics learning motivation questionnaire and giving a test of students’ geometric reasoning abilities. The data analysis technique uses inferential statistics to test normal assumptions and homogeneity and hypothesis testing using the One-Way ANOVA Test. Based on the results of the study showed that the effect of using the STAD type cooperative learning model with the help of GeoGebra was higher when compared to the other two models. That difference occurs at all levels of motivation. On the other hand, the STAD model without GeoGebra only affects high and moderate motivation students. Meanwhile, low motivation students did not show significant differences with the direct learning model.
Exploration towards attitude of students in elementary school teacher education in mathematics learning
Authors: Trisniawati  , Titi Muanifah Mahmudah , Rhosyida Nelly , Adi Widodo Sri , Ardiyaningrum Martalia 
Published: October 2019

AbstractThe purpose of this paper is to know attitude of students of elementary school teacher education towards mathematics learning. The method used in this study is a qualitative approach. The sample is taken using cluster random sampling from second and fourth semester students of elementary school teacher education. Instrument used in this research is questionnaire. The results of the research show that the attitude of elementary school teacher education student at Universitas Sarjanawiyata Tamansiswa towards learning mathematics in the very high category.
Correlation of self-efficacy and mathematical critical thinking skills based on student’s cognitive stage
Authors: Rohaeti E E , Hindun S , Fitriani N 
Published: October 2019

Abstract
Self-efficacy (SE) and critical mathematical thinking skills (MCTS) have been studied extensively. But study about the correlation of both based on student’s cognitive stages (SCS) is rarely done. This study involved 25 students from seventh grade determined by purposive sampling technique in one of the schools in Cimahi. The instrument used the Longeot test, Test of Logical Thinking (TOLT), an Essay MCTS, and a scale of SE. Data analysis performed: percentage calculation, testing of mean difference, and correlations testing at a significance level of 5%. Based on the results and discussion it was concluded that, in general, the SCS classification of seventh grade students based on the Longeot Test and TOLT scores was obtained 24% of students were in the concrete stage, 68% of students were in the transition stage, and 8% of students were in the formal stage. This means that most seventh grade students are in the transition stage. There are differences in MCTS based on SCS in a very weak category. There is no difference in SE based on SCS with enough categories. The relations of SE and MCTS based on SCS is not significant in the low category.
Enhance Learning Independence and Self Ability of Exceptional Children Through Developing Learning Media VBA for Excel Games
Authors: Bernard Martin , Sunaryo Arif , Tusdia Heni , Hendriani Ely , Suhayi Ayi , Nurhidayah  , Parida Mida , Fauzi Ahmad , Rolina Rosalina 
Published: October 2019

Abstract
The aim of this research is to enhance learning independence and self ability of exceptional children. The implementation of learning was assited by the application of VBA for excel games in mathematical learning. The formulation of the problem in this research are whether 1) developing media assisted VBA for excel games can enhance learning independence and self ability of exceptional children? 2) using open ended approach? 3) Did exceptional children have a positive respons in this learning? The approach used in this research is ADDIE which consists of five stage. Population of this study was in group which amounted to 17 samples of exceptional children. The instruments of research are cognitive test and observation. Based on the results of the research, there was an increase in learning independence and self ability of exceptional children through VBA-assisted mathematical learning media for excel games. While the implemention of learning media applied in exceptional children was success. Children showed bravery, active, enthusiastic, responsive, and excited when the process of learning took place.
Mathematical connection ability: teacher’s perception and experience in learning
Authors: Siregar Rosliana , Daut Siagian Muhammad 
Published: October 2019

Abstract
In learning mathematics mathematical connections ability is one of the mathematical ability that must be possessed by students. The strong connection between concepts in mathematics implies that mathematical connections ability also contains other mathematical aspects or vice versa. Viewing mathematics as a whole is very important in learning and thinking about connections between topics in mathematics. This study uses qualitative research methods with phenomenology research design types. The participants in this study were 8 middle school mathematics teachers who taught at different schools. This study uses a short interview form which consists of five open questions to determine the teacher’s understanding of mathematical connection ability. It was found that middle school math teachers had sufficient comprehensive and adequate knowledge of their views on mathematical connection ability, moreover there were also respondents who could not provide examples of mathematical problems that contained the characteristics of mathematical connection ability even though they were able to define what mathematical connection is. Likewise, the development of teachers in mathematical connection ability in learning is still limited to the scope of the relationship of mathematics with mathematics itself and mathematics with everyday life.
Junior High School Students’ Mathematical Reasoning Ability Analysis in Systems of Linear Equations and Applications
Authors: Fisher D , Kusumah Y S , Dahlan J A 
Published: October 2019

Abstract
This study aims to determine students’ mathematical reasoning abilities in systems of linear equations and applications. This research was conducted in the odd semester of the 2018/2019 academic year. The population in this study were all students of class VIII in one of the Junior High Schools in Bandung with a total sample of 32 students. The research instrument used was in the form of a test of mathematical reasoning. The research method used is qualitative research design. Data were analyzed using data reduction, data presentation, and conclusion. Based on the results of the study it can be concluded that the mathematical reasoning ability of junior high school students in SPLDV material is still low.
Pre-Service Mathematics Teachers Divisibility Construction
Authors: Fitrianti Y , Suryadi D , Kusnandi  
Published: October 2019

Abstract
Divisibility concept is fundamental to the development of another concept in elementary number theory. A study of the construction of the divisibility advanced mathematics teacher was done to provide empirical evidence of early genetic decomposition design. Through the question, we designed in the form of test sheets and interview, we explorer the construction of 3 students. The result of this qualitative study illustrated that construction of the divisibility concept on the problem solving of number theory represented in algebra.
The Cognitive Load of Learners in the Learning Process of the Rotating Object Volume
Authors: Wawan  , Ningsih E F , Widodo S A , Leonard  , Sary R M , Retnowati E 
Published: October 2019

Abstract
This research is aimed to explore the cognitive load of learners in the learning process of rotating object volume as well as to provide alternative solutions in managing the intrinsic cognitive load, reducing the extraneous cognitive load as well as improving the germane cognitive load. This research was conducted in Muhammadiyah Purworejo Senior High School with the 3 (three) learners from XII grade as the subjects. The purposive sampling technique was used to determine the research subject. The data collecting method used were test and interview. The data were analyzed by using a qualitative descriptive analysis. This research has provided the results which show that the occurrence of intrinsic cognitive load in the learning process of a rotating object volume is caused by the amount of interactivity elements that have to be studied and the complexity of material learned. The interacting elements are Arithmetic, Algebra, the intersection between two curves, the concept and rule of integration, while the elements of material complexity are the difficulties in imagining the rotating object, and conducting the algebra operation. The occurrence of extraneous cognitive load in the learning process of rotating object volume is caused by the way of teacher delivering the meaningless materials as well as the absence of geometric illustration from the teaching performed by teacher. The next discussion is regarding the germane cognitive load in the learning process of rotating object volume, it is known that this cognitive load is very low. This condition is caused by the learning process in class that tends to be more conventional as well as the minimum activities of learners in studying the materials.
Development of Open-Ended Based Mathematics Problem to Measure High-Level Thinking Ability
Authors: Zulfah  , Astuti  , Insani S U , Zulhendri  , Akbar P 
Published: October 2019

Abstract
The study aims to produce Open-Ended based mathematics problems that can be used to measure the high-level thinking abilities of seventh-grade junior high schools’ students. The study is developmental research using Plomp model, consisting of the preliminary stage, the prototyping stage, and the assessment phase. The subject was seventh-grade students of junior high school. The teaching material used was about numbers learned at seventh-grade junior high school. Based on the results of the development, it was obtained 15 open-ended based problems in which 12 of them possibly have various answers, and 3 have various possibilities ways of answering. The problems developed are valid with the criteria of the developed problem based on content, the problems have diverse answers or various ways to answer, problems can measure high-level thinking skills; analyzing, evaluating, and creating, and the content of the material is fit to the material about numbers. The problems use clear construct images, clear instructions for working on, adapted Standard Indonesian Spelling System or EYD language, and appropriate sentences to seventh-grade knowledge level, disuse of misinterpreted expressions as well. Related to practicality, it is obtained that students and teachers can use the problem and do it well. The teacher can use it to evaluate students’ high-order thinking skills.
Contextual Features of Geometrical Problems in Indonesian Mathematics Textbooks
Authors: Purnomo Y W , Mastura F S , Perbowo K S 
Published: October 2019

AbstractThis study aims to analyze series of Indonesia mathematics textbooks by observing whole tasks and its association with contextual features in geometry topic presented in the textbook. The study was carried out as there are only few studies conducted research on analysis of a textbook for geometry topic. A research method used in the study was textbook research employed in this study to achieve the purpose. The analysis was performed for 9 textbooks from 3 different well-known publishers (Kemendikbud, Erlangga and Yudhistira). Results show that it is more than 25% in average of whole pages in the textbook present geometry topic and there are more than 80% of geometric questions in the textbook belong to intra-mathematical context that is question not related to the real life. Details and further discussion will be elaborated in this paper.
The use of transformative learning in developing students’ self-efficacy
Authors: Rosita Dewi Nur Iyan , Firmansyah Dani 
Published: October 2019

Abstract
The contents from process of learning are individuals changing in cognitive aspect, behaviour, ability and habitual as a product and interaction with its domain. Learning is the process to construct our knowledge by experience transformation. This research objective to analyse the students’ self-efficacy can be increased by transformative learning model. The method in this research is mix method design and the kind of this method is explanatory sequential method. The populations of this research are all of the 2nd grader mathematics education bachelor degree students in Universitas Singaperbangsa Karawang and the samples are 30 students were randomly selected. This research was done in researcher’s own class in order that the subjectivity of data processing and conclusion are maintained.. Data collection methods used is the questionnaire method, learning process observation sheet, documentation, and interview. Data analyse technique used t-test and likert scale. It can be concluded that reviewed based on the overall student and the level of student ability, the students who are given the model of transformative learning have the self-efficacy in carrying out certain tasks or actions needed to achieve desired results better and increased previous. It can be said that the Transformative Learning model can improve students’ self-efficacy
Pedagogical Content Knowledge Pre-Service Mathematics Teacher
Authors: Kadarisma G , Senjayawati E , Amelia R 
Published: October 2019

Abstract
Content knowledge and pedagogical knowledge are two most important aspects of teaching. Therefore, this research is motivated by the importance of pedagogical content knowledge for pre-service teacher students. The purpose of this study is to analyze PCK that is owned by pre-service teachers when teaching quadrilateral material. The method of this study is a qualitative carried out to obtain an in-depth picture of the pre-service teacher’s PCK in the process of learning activities. The sample of this study is taken by 3 students of mathematics teacher candidates who conducting field practice in a junior high school. The instruments of this study are in the form of questionnaires and observation sheets to analyze PCK of teacher candidates, pre-learning questionnaires are used to analyze pre-service teachers in making learning plans as many as 6 indicators, and questionnaires in-learning are used to analyze PCK of teacher candidates in delivering material, mastering concepts and choosing methods in line with 20 Indicators. Based on the data analysis, it was found that the PCK of pre-service teacher students in the quadrilateral material belonged to the classification good enough in developing strategies, making lesson plans, in the learning process and mastery of concepts.
Improving mathematics self-concept through comprehensive mathematics instruction model
Authors: Delima N , Kusumah Y S , Fatimah S 
Published: October 2019

Abstract
The learning process of mathematics in high school now shows that it has not been able to improve students’ mathematics self-concepts. This is indicated by the fact that high school mathematics self-concept students are still relatively low. Therefore, there needs to be an effort to improve these variables, considering that these variables are very important in supporting students’ academic success, especially in mathematics. This study discusses how the implementation of the CMI model in mathematics learning can improve high school mathematics self-concept. This research is a quasi-experimental study. Samples were taken purposively from the population of high school students in Subang, West Java, Indonesia. The instruments used in the study consisted of mathematics self-concept questionnaire and observation sheets. The CMI model is a learning model that accommodates three stages namely develop, solidify and practice. CMI provides many opportunities for students to play an active role in asking questions, explaining the answers to mathematical questions they get, and transferring the knowledge they have with their classmates. The activity will indirectly build the confidence side of students in doing mathematics. The results of the study indicate that the CMI model can improve high school mathematics self-concept.