This research aims to diagnose students' difficulties in solving the TIMSS model mathematics test. This research used quantitative descriptive research method. The subjects of study is eighth-grade students of junior high school in Cirebon, Indonesia. Data collection was carried out through a simple random sampling technique including 676 students of junior high school from 13 public and private schools. The research instrument is the TIMSS modelmathematics test in the form of multiple-choice and short answers as many as 35 items which are translated into Indonesian. Data analysis was using cognitive diagnostic modeling (CDM) in R programe. The research result showen: 1) In the knowing Domian have been dificulties to understand: commutative properties of  on natural numbers, estimating the result of the nearest decimal number, identify the appropriate table with the information on the pictogram graph and read the values of the two line charts; 2) in the applaying Domian have been dificulties in: choose and combine information from two different sources to solve problems with multiple steps and in the number series, in find solutions in linear equations of two variables, compiling and using solutions of linear equations to solve problems, and calculating the side lengths of triangles based on linear equations, symmetry properties of reflection and using information from tables to draw a bar chart and compare two possible events; (3) In reasoning domain have been dificulties in to find number patterns and to use the Pythagorean theorem to find the perimeter of a quadrilateral or triangle

Diagnostic’s Analysis; Student’s difficulties; TIMSS; CDM

Abidin, M., & Retnawati, H. (2019). A diagnosis of difficulties in answering questions of circle material on junior high school students. Jurnal Penelitian Dan Evaluasi Pendidikan, 23(2). https://doi.org/10.21831/pep.v23i2.16454

Adi, N. R. M. (2019). Pengembangan Tes Model TIMSS untuk Mengukur Kemampuan Matematika Siswa Kelas VIII dan Analisnya Menggunakan Model Rasch. Program Studi Penelitian dan Evaluasi Pendidikan Pascasarjana Universitas Negeri Semarang: Semarang.

Al-Amin, Y., & Murtiyasa, B. (2021). Analisis Kesulitan Belajar Aritematika pada Proses Pembelajaran Daring Menggunakan Metode Pembelajaran Berbasis Masalah. Kontinu: Jurnal Penelitian Didaktik Matematika, 5(1), 49–62. https://doi.org/http://dx.doi.org/10.30659/kontinu.5.1.49-65

Gierl, M. J., Zheng, Y., & Cui, Y. (2008). Using the Attribute Hierarchy Method to Identify and Interpret Cognitive Skills that Produce Group Differences. Journal of Educational Measurement, 45(1), 65–89. https://doi.org/10.1111/j.1745-3984.2007.00052.x

Ina V.S. Mullis, Michael O. Martin, Pierre Foy, and A. A. (2012). Timss 2011 International Results in Mathematics. In TIMSS & PIRLS International Study Center: Boston.

Isgiyanto, A. (2013). Diagnosis Kesalahan Siswa Berbasis Penskoran Politomus Model Partial Credit pada Matematika. Jurnal Penelitian Dan Evaluasi Pendidikan, 15(2), 308–325. https://doi.org/10.21831/pep.v15i2.1099

Laamena, C. M., & Laurens, T. (2020). Development of Integer Number Learning Devices Using Moluccas Local Wisdom . EduMa: Mathematics Education Learning And Teaching , 10(1), 60–70. https://doi.org/http://dx.doi.org/10.24235/eduma.v10i1.8163

Mahmud, M. R., & Pratiwi, I. M. (2019). Literasi Numerasi Siswa dalam Pemecahan Masalah Tidak Terstruktur. KALAMATIKA Jurnal Pendidikan Matematika, 4(1), 69–88. https://doi.org/10.22236/KALAMATIKA.vol4no1.2019pp69-88

Mullis, I. V. S., Martin, M. O., Foy, P., & Hooper, M. (2016). TIMSS 2015 International Results in Mathematics. . In TIMSS & PIRLS International Study Center: Boston.

Munaji, & Setiawahyu, M. I. (2020). Profil Kemampuan Matematika Siswa SMP di Kota Cirebon Berdasarkan Standar TIMSS. Terorema: Teori Dan Riset Matematika, 5(2), 249–262. https://doi.org/http://dx.doi.org/10.25157/teorema.v5i2.3732

Noto, M. Su., Pramuditya, S. A., & Handayani, V. D. (2020). Exploration of Learning Obstacle Based on Mathematical Understanding of Algebra in Junior High School. EduMa: Mathematics Education Learning And Teaching , 9(1), 14–20. https://doi.org/:http://dx.doi.org/10.24235/eduma.v9i1.5946

Nurhayati, & Zanthy, L. S. (2019). Analisis Kemampuan Pemecahan Masalah Matematik Siswa MTs pada Materi Pola Bilangan. Journal On Education, 1(2), 23–35. https://doi.org/https://doi.org/10.31004/joe.v1i2.49

Prasetyo, D. A. B., & Rudhito, M. A. (2016). Simposium Nasional Inovasi dan Pembelajaran Sains 2016. Analisis Kemampuan Dan Kesulitan Siswa Dalam Menyelesaikan Soal Geometri Model TIMSS , 275–283.

Ravand, H., & Robitzsch, A. (2015). Cognitive diagnostic modeling using R. Practical Assessment, Research and Evaluation, 20(11), 1–12. https://doi.org/https://doi.org/10.7275/5g6f-ak15

Retnawati, H. (2017). Diagnosing The Junio High School Student’s Difficulties In Learning Mathematics. International Journal on New Trends in Education and Their Implications , 8(1), 33–50.

Utari, D. R., Wardana, M. Y. S., & Damayani, A. T. (2019). Analisis Kesulitan Belajar Matematika dalam Menyelesaikan Soal Cerita. Jurnal Ilmiah Sekolah Dasar , 3(4), 534–540. https://doi.org/http://dx.doi.org/10.23887/jisd.v3i4.22311

Wardhani, S., & Rumiati. (2011). Instrumen Penilaian Hasil Belajar Matematika SMP: Belajar dari TIMSS dan PISA. Kementrian Pendidikan Nasional Badan Pengembangan Sumber Daya Manusia Pendidikan dan Penjamin Mutu Pendidikan Pusat Pengembangan dan Pemberdayaan Pendidikan dan Tenaga Kependidikan (PPPPTK) Matematika: Yogyakarta.