THE DEVELOPMENT OF MENTAL MODELS TEST ON HEAT AND TEMPERATURE

We have developed test inventory as an analysis of mental models on heat and temperature topics. This development research based on the importance of knowing the level of students' mental models. The mental models are a student’s internal representation of understanding a concept. This study uses a 4-D model. The product being produced is a mental model analysis consists of open-ended questions. Furthermore, mental models test were tested on respondents (N = 90) to measure the validity and reliability. The test that has been developed consists of 8 questions with a value of reliability is 0.667. Based on data analysis, the test of mental models on heat and temperature topics is feasible to use as an assessment instrument.


INTRODUCTION
Physics is one of the lessons in a secondary school which has many concepts. Physics concepts can be understood through two dimensions of knowledge that is macroscopic and microscopic dimensions (Kantarinata et al., 2017). The macroscopic dimension used to understand the physics concepts through daily experience and can be observed directly (Kurnaz & Emen, 2014;Priyadi et al., 2019). The microscopic dimension used to understand physics concepts based on smaller views, for example, interactions between molecules, energy flows, waves, and others (Amrizaldi et al., 2014;Jansoon et al., 2009;Kurnaz & Emen, 2014).
Students' understanding of the microscopic dimension can assist them in understanding the concept of physics-based on the macroscopic dimension (Albaiti et al., 2016;Priyadi et al., 2018). One topic of physics that requires understanding in the microscopic dimension is heat and temperature (Amrizaldi et al., 2014;Kantarinata et al., 2017). This is because heat and temperature topics can be studied through daily life phenomena (Amalia et al., 2017;Chu et al., 2012), for example, expansion and heat transfer phenomenon. Through the microscopic dimension, students can understand the occurrence of this phenomenon through physics concepts.
Students' understanding of these two dimensions will affect the way students think about physics concepts, especially in heat and temperature. Students who can understand both dimensions will find it easy to solve physics problems related to phenomena that occur (Chermack et al., 2012;Jansoon et al., 2009;Priyadi et al., 2018). The ability of students to solve any given problems determines the level of mental models they have.
Initially, research on mental models was the research in the cognitive psychology field. This research was conducted to study how students learn, remember (Rook, 2013;Sternberg, 2009), think (Shute et al., 2009), and to know systematic explanations (Pitt, 2017). Based on this description, Mental models can be applied to evaluate students' level of understanding of physics concepts (Corpuz & Rebello, 2011;Didiş et al., 2014;Rahayu & Purwanto, 2013).
Information about the level of students' mental models can be known through assessment. For example, assessment on how students' ability to explain the state of atoms when expansion occurs (Kurnaz & Emen, 2014). Assessment of mental models through interviews, linguistic analysis, or open-ended questions (Corpuz & Rebello, 2011;Johnson-Laird, 2013).
The students' answer becomes a reference to determine the level of mental models they have. There are many methods for determining the level of students mental models, i.e., ACSMM, MITOCAR, SMD, DEEP, SSI, and PDE (Al-Diban & Ifenthaler, 2011;Johnson et al., 2006;Langan-Fox, Code, & Langfield-Smith, 2000;Priyadi et al., 2018). Nowadays, mental model research has progressed and is a major attraction for researchers to understand how students think. However, the availability of model mental tests is still difficult to find, if mental models test is available, it will help educators and other researchers to access students' mental models. Based on the problems, this study aims to produce mental model tests, especially on heat and temperature.

METHOD
This study is a development research that produces mental models test and used the 4-D model (Tiagarajan et al., 1974). The step carried out in each 4-D stage are presented in Table 1.

Define
Based on preliminary analysis, it is still difficult to find tests of mental models in physics, especially on heat and temperature. The limitations of mental model tests on the topic of physics are the main reason for developing mental model tests. The availability of many mental model tests will help educators and other researchers to explore mental models possessed by students.

Design
In this step, we analyze the competencies of heat and temperature in mathematics and science classes in senior high school. Furthermore, from the competency analysis, four indicators must be achieved during learning. Competencies and indicators are present in Table 2.

Develop
Based on the indicators in Table 2. Mental model tests were developed as open-ended questions. Each question consists of three items that are useful for classifying students' mental models. One example of a developed mental model test presented in Table 2. After the questions were developed, a trial was then conducted on 90 respondents to see the validity and reliability of the test. Based on data analysis, the results of the validity and reliability of the mental models' test are presented in Table 3.

Disseminate
The developed test is then implemented to determine the level of student's mental models. To determine the level of students' mental models, the method used is SSI. There are three levels of mental models, i.e., scientific, synthetic, and initial.
The mental model level is categorized using rubrics, which are divided into two rubrics, i.e., descriptions analyze rubric and visuals analyze rubric. The descriptions analyze rubric is present in Table 4, and the visuals analyze rubric is present in Table 5.

Levels Criteria Sound Understanding (SU)
The answer contains all scientific response components.

Partial Understanding (PU)
The answer contains half the response component.

Partial Understanding with Alternative Conception (PU-AC)
Answers like to PU level, but other concepts are not appropriate.

Alternative Conception (AC)
The answer is scientifically wrong and contains incorrect.

No Understanding (NU)
Not answer.

Partial Correct Depicting (PCD)
Answers reflect half the components of scientific description.

Correct
Drawing also reflecting Nonscientific Depicting (CD-ND) Answers like to the PCD level, but some descriptions are not appropriate or not scientifically accepted.

Incorrect Depicting (ID)
The answer reflects a description that is not scientific.

No Depicting (ND)
Not answer.
Source: Kurnaz & Eksi (2015) After analyzing students' answers, they are classified according to the level of mental models (scientific, synthetic, or initial) presented in Table  6.

Levels Criteria Scientific
The perception that coincides with PU or PCD / SU or CD.

Synthetic
The perception which is partially located or not by knowledge Initial The perception that is not by knowledge. Answers are at NU or ND / AC or ID / PU-AC or CD-ND.
Source: Kurnaz & Eksi (2015) The scientific level that describes students thinking scientifically on each concept is that they can relate the phenomenon to an appropriate concept. The synthetic level describes that students are not consistent in using concepts. Sometimes, they use concepts that are not relevant when solving problems. The initial level that describes students unable to connect phenomena that arise with an actual concept (Abraham et al., 1994;Kurnaz & Eksi, 2015).
The research subjects in this step are 11thgrade students of mathematics and science in-state senior high school 4 of Malang, consisting of two classes. The use of two classes aims to assess the accuracy of developed mental model tests. The accuracy of mental models test in each class based on indicators is present in Figure 2. explains that dominant students have mental models at the synthetic level on indicators 1, 2, and 3 in each class. Whereas indicators numbers 4 and 5 show different results, the majority of students in class A are at a scientific level and class B is at a synthetic level. Therefore, the test instruments that have been produced can distinguish the level of students' mental models.

CONCLUSION
Test instruments have been developed as an analysis of students' mental models on heat and temperature topic. The test consisted of 8 items of mental models that were valid and had a value of reliability is 0.667. Based on the results, it was concluded that mental model tests on heat and temperature were suitable for use as analyzes of students' mental models. Future studies are expected to develop a mental model tests on other physics concepts.