Mathematical Representation Ability (MRE) is one of the important competencies that need to be mastered by students in learning mathematics. One aspect that can affect students' MRE is the character or thinking patterns possessed by the students. This study aims to evaluate the level of validity and reliability of the test instrument designed to measure the mathematical representation ability of junior high school students in solving algebra problems. The method used is a quantitative descriptive method. Based on the results of the validity test using the Aiken's V formula, the four questions were said to be valid, which indicates that the instrument has very good validity and is suitable for use. Meanwhile, the results of the reliability test showed a correlation coefficient value of 0.795, which indicates a fairly good level of consistency in the reliability category so that it is considered reliable. Thus, this instrument is considered suitable for use by teachers in measuring students' mathematical representation abilities in algebra material.

Al Hakim, R., Mustika, I., & Yuliani, W. (2021). Validitas dan Reliabilitas Angket Motivasi Berprestasi. FOKUS (Kajian Bimbingan & Konseling Dalam Pendidikan), 4(4), 263-268. https://doi.org/10.22460/fokus.v4i4.7249

Andini, H. P., Sunismi, & Setiawan, Y. E. (2021). Analisis Kemampuan Representasi Matematis pada Pokok Bahasan Teorema Pythagoras Ditinjau dari Self Efficacy Siswa Kelas VIII SMP. Jurnal Penelitian, Pendidikan, dan Pembelajaran, 16(25). https://jim.unisma.ac.id/index.php/ jp3/article/download/13928/10711

Anggraini, F. D. P., Aprianti, Setyawati, V. A. V., & Hartanto, A. A. (2022). Pembelajaran Statistika Menggunakan Software SPSS untuk Uji Validitas dan Reliabilitas. Jurnal Basicedu, 6(4), 6491- 6504. https://dx.doi.org/10.31004/basicedu.v6i4.3206

Ardiansyah, Risnita, & Jailani, M. S. (2023). Teknik Pengumpulan Data Dan Instrumen Penelitian Ilmiah Pendidikan Pada Pendekatan Kualitatif dan Kuantitatif. IHSAN: Jurnal Pendidikan Islam, 1(2), 1-9. https://doi.org/10.61104/ihsan.v1i2.57

Chen, Q., Liang, C., Lu, J., & Jiang, Z. (2024). Translation and validation of the chinese version of the self-awareness scale for nurses. Frontiers in Public Health, 12. https://doi.org/10.3389/fpubh.2024.1352983

Erbilgin, E. and Şahin, B. (2021). The effects of a professional development program for technology integrated algebra teaching. Research in Educational Policy and Management, 3(2), 1-21. https://doi.org/10.46303/repam.2021.4

Gabrielsson, S., Engström, Å., & Gustafsson, S. (2019). Evaluating reflective practice groups in a mental health context: swedish translation and psychometric evaluation of the clinical supervision evaluation questionnaire. BMC Nursing, 18(1). https://doi.org/10.1186/s12912-019-0326-2

Hardianti, S. R., & Effendi, K. N. S. (2021). Analisis kemampuan representasi matematis siswa SMA kelas XI. JPMI (Jurnal Pembelajaran Matematika Inovatif), 4(5), 1093-1104. https://doi.org/10.22460/jpmi.v4i5.p1093-1104

Herdiana, Y., Marwan, & Zubainur, C. M. (2019). Kemampuan Representasi Matematis dan Self Confidence Siswa SMP Melalui Penerapan Model Problem Based Learning (PBL). Jurnal Ilmiah Pendidikan Matematika Al Qalasadi, 3(2), 23-35. https://doi.org/10.32505/qalasadi.v3i2.1250

Hikmah, & Muslimah. (2021). Validitas dan Reliabilitas Tes dalam Menunjang Hasil Belajar PAI. In Proceedings of Palangka Raya International and National Conference on Islamic Studies (PINCIS), 1(1). https://e-proceedings.iain-palangkaraya.ac.id/index.php/ PICIS/ article/ download/520/855

Huda, U., Musdi, E., & Nari, N. (2019). Analisis Kemampuan Representasi Matematis Siswa Dalam Menyelesaikan Soal Pemecahan Masalah Matematika. Ta'dib, 22(1), 19-26. http://dx.doi.org/10.31958/jt.v22i1.1226

Júnior, C. J. d. S., Silva, M. R. d., & Costa, P. J. M. d. S. (2024). Psychometric properties and reliability of the brazilian version of parent attitudes about childhood vaccine (pacv-br). Revista Paulista De Pediatria, 42. https://doi.org/10.1590/1984-0462/2024/42/2023019

Leppink, J. and Pérez-Fuster, P. (2017). We need more replication research – a case for test-retest reliability. Perspectives on Medical Education, 6(3), 158-164. https://doi.org/10.1007/s40037-017-0347-z

Lestari & Suryadi (2020). Analisis Kesulitan Operasi Hitung Bentuk Aljabar. Juring (Journal for Research in Mathematics Learning) (2020) doi:10.24014/juring.v3i3.9737

Milkhaturrohman, Silva, S. D., & Wakit, A. (2022). Analisis Kesulitan Belajar Matematika Materi Bangun Datar di SDN 2 Mantingan Jepara. Mathema: Jurnal Pendidikan Matematika, 4(2), 94- 106. https://doi.org/10.33365/jm.v4i2.2095

Mohammad, W. M. Z. W., Arifin, W. N., Shafei, M. N., Sukeri, S., Idris, Z., Bakar, R. A., … & Aziah, D. (2018). Development and validation of a new knowledge, attitude, belief and practice questionnaire on leptospirosis in malaysia. BMC Public Health, 18(1). https://doi.org/10.1186/s12889-018-5234-y

Mufidah, A. (2021). Analisis Validitas dan Reliabilitas Instrumen Pengukuran Mengenal Bentuk-Bentuk Geometri. Jurnal Kualita Pendidikan, 2(3). https://doi.org/10.51651/jkp.v2i3.144

Mulyaningsih, S., Marlina, R., & Effendi, K. N. S. (2020). Analisis Kemampuan Representasi Matematis Siswa SMP dalam Menyelesaikan Soal Matematika. JKPM (Jurnal Kajian Pendidikan Matematika), 6(1), 99-110. http://dx.doi.org/10.30998/jkpm.v6i1.7960

Nasution, H. F. (2016). Instrumen Penelitian dan Urgensinya Dalam Penelitian Kuantitatif. Al-Masharif: Jurnal Ilmu Ekonomi Dan Keislaman, 4(1), 59-75. https://doi.org/10.24952/masharif.v4i1.721

Nasution, Z. M., Surya, E., & Manullang, M. (2017). Perbedaan Kemampuan Pemecahan Masalah Matematik dan Motivasi Belajar Siswa yang Diberi Pendekatan Pembelajaran Berbasis Masalah dengan Pendidikan Matematika Realistik di SMP Negeri 3 Tebing Tinggi. Paradikma, 10(1). https://dx.doi.org/10.24114/paradikma.v10i1.8688

National Council of Teachers of Mathematics. (2000). Principles and Standards for School Mathematics. National Council of Teachers of Mathematics.

Rahayu, N. S., & Afriansyah, E. A. (2021). Miskonsepsi Siswa SMP Pada Materi Bangun Datar Segiempat. Plusminus: Jurnal Pendidikan Matematika, 1(1), 17-32. https://karya.brin. go.id/16035/1/Jurnal_Nisa%20Sri%20Rahayu_MTs%20Manbaul%20Huda%20Garut_2021.pdf

Rahayu, S., & Hidayati, W. N. (2018). Meningkatkan Hasil Belajar Matematika Melalui Penggunaan Media Bangun Ruang dan Bangun Datar Pada Siswa Kelas V SDN Jomin Barat I Kecamatan Kotabaru Kabupaten Karawang. JPsd (Jurnal Pendidikan Sekolah Dasar), 4(2), 204-215. http://dx.doi.org/10.30870/jpsd.v4i2.3854.g2785

Ratnasari, N., Tadjudin, N., Syazali, M., Mujib, M., & Andriani, S. (2018). Project based learning (pjbl) model on the mathematical representation ability. Tadris: Jurnal Keguruan Dan Ilmu Tarbiyah, 3(1), 47-53. https://doi.org/10.24042/tadris.v3i1.2535

Ruspa & Marlina (2022). SURVEI PERAN ORANGTUA DALAM MENUNJANG PENDIDIKAN ANAK DI RUMAH DAN DI SEKOLAH DI TAMAN KANAK-KANAK ISLAM BAKTI 53. JCE (Journal of Childhood Education) (2022) doi:10.30736/jce.v6i2.1058

Rusnianti, W. O., Kaimuddin, L. O., Kansil, Y. E. Y., & Ashari, I. (2021). Analisis Kesulitan Siswa Belajar Matematika Pada Materi Bangun Datar Kelas IV SD Negeri 5 Buton. Jurnal Ilmiah Pembelajaran Sekolah Dasar, 3(2). http://ojs.uho.ac.id/index.php/jipsd

Sari, A. R., & Aripin, U. (2018). Analisis Kesalahan Siswa Dalam Menyelesaikan Soal Cerita Bangun Datar Segiempat Ditinjau Dari Kemampuan Pemecahan Masalah Matematik Untuk Siswa Kelas VII. JPMI (Jurnal Pembelajaran Matematika Inovatif), 1(6), 1135-1142. https://doi.org/10.22460/jpmi.v1i6.p1135-1142

Sari & Nasution (2023). ANALISIS KEMAMPUAN BERPIKIR ALJABAR SISWA KELAS IX A SMP NEGERI 12 KOTA SUNGAI PENUH PADA MATERI SPLDV. Jurnal Riset Pembelajaran Matematika (2023) doi:10.55719/jrpm.v5i2.580

Setiyawan, R. A., & Wijayanti, P. S. (2020). Analisis Kualitas Instrumen Untuk Mengukur Kemampuan Pemecahan Masalah Siswa Selama Pembelajaran Daring di Masa Pandemi. Jurnal Lebesgue: Jurnal Ilmiah Pendidikan Matematika, Matematika Dan Statistika, 1(2), 130-139. https://doi.org/10.46306/lb.v1i2.26

Sormin, R. P. A. and Ratuanik, M. (2023). Analysis of students' mathematical representation ability in solving divergen mathematics problems in view of gender differences. Jurnal Eduscience, 10(1), 264-272. https://doi.org/10.36987/jes.v10i1.3805

Suhardi, I. (2022). Perangkat Instrumen Pengembangan Paket Soal Jenis Pilihan Ganda Menggunakan Pengukuran Validitas Konten Formula Aiken's V. Jurnal Pendidikan Tambusai, 6(1), 4158-4170. https://doi.org/10.31004/jptam.v6i1.3519

Sulistyawati, W., Wahyudi, & Trinuryono, S. (2022). Analisis (Deskriptif Kuantitatif) Motivasi Belajar Siswa Dengan Model Blended Learning Di Masa Pandemi Covid19. Kadikma, 13(1), 68-73. https://jurnal.unej.ac.id/index.php/kadikma/article/download/31327/11235/

Syabaniah, T. N., & Nuraeni, Z. (2023). Kemampuan Representasi Matematis Siswa SMP Menggunakan Instructional Video Berbasis Pendekatan Worked Example. Jurnal THEOREMS (The Original Research of Mathematics), 7(2), 321-336. http://dx.doi.org/10.31949/th.v7i2.4515

Tampubolon, J., Atiqah, N., & Panjaitan, U. I. (2019). Pentingnya Konsep Dasar Matematika Pada Kehidupan Sehari-hari Dalam Masyarakat. Tampubolon, J., Atiqah, N., & Panjaitan, U. I. (2019). Pentingnya konsep dasar matematika pada keProgram Studi Matematika Universitas Negeri Medan, 2(3). https://osf.io/zd8n7/download

Tumanggor, A. M. R. and Supahar, S. (2021). Dissemination of online diagnostic test instrument to diagnose high school students’ mathematical representation ability: the case of work and energy. Advances in Social Science, Education and Humanities Research. https://doi.org/10.2991/assehr.k.210326.076

Ünal, Z. E., Aslı, M., Kartal, G., Özel, S., & Geary, D. C. (2023). Visual and symbolic representations as components of algebraic reasoning. Journal of Numerical Cognition, 9(2), 327-345. https://doi.org/10.5964/jnc.11151

Vrinten, J., Royen, K. V., Pabian, S., Backer, C. D., & Matthys, C. (2023). Development and validation of a short nutrition literacy scale for young adults. Frontiers in Nutrition, 10. https://doi.org/10.3389/fnut.2023.1008971

Wibawa, K. A. (2019). Fragmentation of the thinking structure of translation in solving mathematical modelling problems. Southeast Asian Mathematics Education Journal, 9(1), 25-36. https://doi.org/10.46517/seamej.v9i1.71

Wibowo, C., Dese, D. C., & Nopiyanto, Y. E. (2024). Developing a precise gross motor skills assessment instrument for elementary school students (ages 7-9). Pedagogy of Physical Culture and Sports, 28(2), 84-92. https://doi.org/10.15561/26649837.2024.0201

Wijaya, C. B. (2018). Analisis Kemampuan Representasi Matematis Siswa Dalam Menyelesaikan Soal Lingkaran Pada Kelas VII-B MTs Assyafi’iyah Gondang. Suska Journal of Mathematics Education, 4(2), 115-124. http://dx.doi.org/10.24014/sjme.v4i2.5234

Yeng, T., O’Sullivan, A. J., & Shulruf, B. (2021). Medical students’ perception of an online dental trauma course in medical education. Australian Endodontic Journal, 48(1), 51-57. https://doi.org/10.1111/aej.12601