Damjan Krstajic Bio

I am a freelancer with 25 years of experience in software development, software testing, machine learning, and general predictive modelling. I have developed and maintained several automated machine learning systems, as well as systems for testing them. I like to design in advance, write nice and neat code, test as much as possible, and to finish my work with proper documentation. I enjoy solving practical scientific problems and tackling complex statistical issues.

Over the last two decades I have had 3 long professional collaborations with prof dr David E Leahy (25 years), dr Ljubomir Buturovic (10 years) and dr Simon Thomas (over 15 years).

I am proud of our paper on cross-validation pitfalls (over 900 citations), my critical assessment of conformal predictions and my work on "I don't know" predictions.

Since 2007, as the director of the Research Centre for Cheminformatics in Serbia, we have been exporting scientific computing, predictive models, and statistical consultancy to clients in the UK and USA. Below is the list of major clients:

  • OncoStem Diagnostics (India)
  • Opportunity Pharma (UK)
  • Inflammatix (USA)
  • Clinical Persona (USA)
  • Cyprotex (UK)
  • Pathwork Diagnostics (USA)
  • Northern Institute of Cancer Research (UK)
  • Institute for Cancer Research (UK)
  • Cancer Research Technology (UK)
  • I have a statatistical consultancy company Stat Centar

    My Google Scholar.

    I publish newspaper articles on a regular basis in leading Serbian newspapers (Politika and Danas) on various subjects, but mostly regarding science and statistics.

    In my spare time I develop the aloom R package.


    1. Neznanje u veštačkoj inteligenciji (en. Ignorance in artificial intelligence)
      Damjan Krstajic
      6th October 2021, Mathematical Institute, Serbian Academy of Science (Virtual)

    Book chapters:

    1. Non-applicability Domain. The Benefits of Defining “I Don't Know” in Artificial Intelligence
      Damjan Krstajic
      Artificial Intelligence in Drug Discovery (Chapter 6)

    Scientific publications:

    1. Critical Assessment of Conformal Prediction Methods Applied in Binary Classification Settings
      Damjan Krstajic
      Journal of Chemical Information and Modeling 2021 61 (10), 4823-4826
      DOI: 10.1021/acs.jcim.1c00549
    2. The Costs and Potential Benefits of Introducing the “I Don’t Know” Answer in Binary Classification Settings
      Damjan Krstajic
      Preprints 2021, 2021080521 (doi: 10.20944/preprints202108.0521.v1)
    3. Missed opportunities in large scale comparison of QSAR and conformal prediction methods and their applications in drug discovery
      Damjan Krstajic
      Journal of Cheminformatics (2019)
    4. No association between donor telomere length and outcomes after allogeneic unrelated hematopoietic cell transplant in patients with acute leukemia
      S. Gadalla, T. Wang, D. Loftus, L. Friedman, C. Dagnall, M. Haagenson, S.R Spellman, L. Buturovic, M. Blauwkamp, J. Shelton, K. Fleischhauer, K.C. Hsu, M.R. Verneris, D. Krstajic, B. Hicks, K. Jones, S.J. Lee, S.A. Savage
      Bone Marrow Transplantation (2017)
    5. Binary classification models with Uncertain predictions
      D. Krstajic, L. Buturovic, S. Thomas, D.E. Leahy
    6. How real is the random censorship model in medical studies?
      Damjan Krstajic
    7. Why comparing survival curves between two prognostic subgroups may be misleading
      Damjan Krstajic
    8. Derivation of gene expression classifiers for the non-invasive detection of bladder cancer in the hematuria and recurrence surveillance populations.
      Chapman, K.B., Buturovic, L., Qiu, L., Kidd, J., Sheibani, N., Krstajic, D., Friedman, L., Bailen, J.L., Dumbadze, I., Saltzstein, D.R. and Olson, M.T.
      Journal of Clinical Oncology 2016 ASCO Annual Meeting Proceedings (Vol. 34, No. 15_suppl, p. 11522)
    9. Reproducibility of telomere length assessment
      D. Krstajic, L. Buturovic
      Int. J. Epidemiol. (2015) doi: 10.1093/ije/dyv167
    10. Cross-validation pitfalls when selecting and assessing regression and classification models.
      D. Krstajic, L.J. Buturovic, D.E. Leahy, S. Thomas
      Journal of Cheminformatics 6(1): 10 (2014)
    11. Raising awareness of fungi in Serbia
      D. Krstajic
      Fungal Conservation, 2012 April; Issue 2: 23-26
    12. Hemodynamic Flow Modeling Through an Abdominal Aorta Aneurysm Using Data Mining Tools.
      N. Filipovic, M. Ivanovic, D. Krstajic, M. Kojic
      IEEE Transactions on Information Technology in Biomedicine 15(2): 189-194 (2011)
    13. Competitive Workflow: novel software architecture for automating drug design
      J. Cartmell, D. Krstajic, D. E. Leahy
      Current Opinion in Drug Discovery & Development, 2007 May; 10(3): 347-352
    14. Automated QSPR through Competitive Workflow
      J.Cartmell, S. Enoch, D. Krstajic, D. E. Leahy
      Journal of Computer Aided Molecular Design, 2005 Nov; 19(11): 821-833

    Popular articles published in Serbian newspapers:

    1. Zloupotreba statistike u nauci Danas 28th July 2017 (PDF with references)
    2. Ko proverava naučne nalaze Politika (Kulturni dodatak) 23rd September 2017 (PDF with references)
    3. Neuspesi u naučnim istraživanjima Politika (Kulturni dodatak) 6th January 2018 (PDF with references)
    4. Da li su objavljeni istraživački nalazi većinom pogrešni Politika (Kulturni dodatak) 17th February 2018 (PDF with references)
    5. Benigni profiteri nauke Politika (Kulturni dodatak) 10th March 2018 (PDF with references)
    6. Skriveni uzroci Politika (Kulturni dodatak) 31st March 2018 (PDF with references)
    7. Kome danas verovati u nauci Politika (Kulturni dodatak) 5th May 2018 (PDF with references)
    8. Ispravljanje grešaka u nauci Politika (Kulturni dodatak) 2nd June 2018 (PDF with references)
    9. Šta znamo da ne znamo u nauci Politika (Kulturni dodatak) 14th July 2018 (PDF with references)
    10. Hiperprodukcijom radova do zasićenja u nauci Politika (Kulturni dodatak) 25th August 2018 (PDF with references)
    11. Zašto 5 odsto? Politika (Kulturni dodatak) 10th November 2018 (PDF with references)
    12. Nauka ne samo radi nauke Politika (Kulturni dodatak) 8th December 2018 (PDF with references)
    13. Teorija slučajne nesreće Politika (Kulturni dodatak) 12th January 2019 (PDF with references)
    14. Drugačiji pogled na statistiku Politika (Kulturni dodatak) 26th January 2019 (PDF with references)
    15. Demistifikacija veštačke inteligencije Politika (Kulturni dodatak) 2nd March 2019 (PDF with references)
    16. (Ne)razuman strah od veštačke inteligencije Politika (Kulturni dodatak) 9th March 2019 (PDF with references)
    17. Naučno dokazano Politika (Kulturni dodatak) 26th October 2019 (PDF with references)
    18. U odbranu Svetislava Basare Danas 27th November 2019
    19. Klimatska apokalipsa Politika (Kulturni dodatak) 28th December 2019 (PDF with references)
    20. Posmatraj - Orijentiši se - Odluči - Pokreni Politika (Kulturni dodatak) 25th January 2020 (PDF with references)
    21. Orijentacija u nauci Politika (Kulturni dodatak) 1st February 2020 (PDF with references)
    22. Populacija i reprezentativan uzorak Politika (Kulturni dodatak) 28th March 2020 (PDF with references)
    23. Statistike dijagnostičkih testova Politika (Kulturni dodatak) 10th April 2020 (PDF with references)
    24. Zbunjujući faktor Politika (Kulturni dodatak) 24th April 2020 (PDF with references)
    25. Rasprostranjenost indukcije Politika (Kulturni dodatak) 4th July 2020 (PDF with references)
    26. Neznanje u veštačkoj inteligenciji Politika (Kulturni dodatak) 26th December 2020 (PDF with references)
    27. Milove induktivne metode Politika (Kulturni dodatak) 16th January 2021 (PDF with references)
    28. Statistika i uzročnost Politika (Kulturni dodatak) 30th January 2021 (PDF with references)
    29. Opovrgljivost naučnih teorija Politika (Kulturni dodatak) 6th February 2021 (PDF with references)
    30. Centralno u statistici Politika (Kulturni dodatak) 27th February 2021 (PDF with references)
    31. Ne postoji apsolutno bezbedno Politika (Kulturni dodatak) 13th March 2021 (PDF with references)
    32. Umeće prezentacije nauke Politika (Kulturni dodatak) 24th April 2021 (PDF with references)
    33. Srednjoškolski udžbenik za sve nas Politika (Kulturni dodatak) 7th August 2021 (PDF with references)
    34. Literatura o veštačkoj inteligenciji Politika (Kulturni dodatak) 21st August 2021 (PDF with references)
    35. To se (ne) može prevesti Politika (Kulturni dodatak) 18th September 2021 (PDF with references)
    36. Zašto ne volim našu reč dokaz Politika (Kulturni dodatak) 16th October 2021 (PDF with references)
    37. Uzročnost u medicini Politika (Kulturni dodatak) 6th November 2021 (PDF with references)
    38. Piramida pouzdanosti u medicini Politika (Kulturni dodatak) 13th November 2021 (PDF with references)
    39. Biruni - veliki persijski naučnik Politika (Kulturni dodatak) 18th December 2021 (PDF with references)
    40. Individualni poroci i javna korist Politika (Kulturni dodatak) 8th January 2022 (PDF with references)
    41. Problematika razumevanja satire Danas 28th February 2022
    42. Vreme kao kvantitet i kao kvalitet Politika (Kulturni dodatak) 26th March 2022 (PDF with references)
    43. Sudbina takmičara iz Matematičke gimnazije Danas 5th April 2022
    44. Može i bez pretnji Danas 16th April 2022
    45. Klozetsko pitanje u našim školama Danas 5th May 2022
    46. Zvučni pejzaž koji stvaramo Danas 11th May 2022
    47. Zahvaljivanje našim sugrađanima Danas 15th June 2022
    48. Kultura i umeće pisane kritike Danas 30th June 2022
    49. Mi dobri, Oni loši Politika (Kulturni dodatak) 6th August 2022 (PDF with references)
    50. Mnoštvo podataka u nauci je ozbiljan problem Danas (dodatak Nedelja) 10th September 2022 (PDF with references)
    51. „Manje“ vredni životi 50 devojaka Danas 20th October 2022
    52. Kako je britanski Azijat postao premijer Danas (dodatak Nedelja) 5th November 2022 (PDF with references)
    53. Duboko slušanje Danas 15th December 2022
    54. Za i protiv Danas 5th January 2023
    55. Pristrasnost u razumevanju verovatnoće Politika (Kulturni dodatak) 28th January 2023 (PDF with references)
    56. Mimovi za mlađe, memi za starije Politika (Kulturni dodatak) 11th February 2023 (PDF with references)
    57. Dama koja razlikuje engleski čaj Politika (Kulturni dodatak) 25th February 2023 (PDF with references)
    58. Evolucija nežive materije Politika (Kulturni dodatak) 11th March 2023 (PDF with references)
    59. Ispravno data pogrešna terapija Politika (Kulturni dodatak) 25th March 2023 (PDF with references)
    60. Da li talenat može da se istroši pre vremena Politika (Kulturni dodatak) 22nd April 2023 (PDF with references)
    61. Posvećeno istraživanje gljiva Politika (Kulturni dodatak) 17th June 2023 (PDF with references)
    62. Koliko vredi dobar profesor Politika (Kulturni dodatak) 8th July 2023 (PDF with references)
    63. Osnovno nerazumevanje nauke Politika (Kulturni dodatak) 22nd July 2023 (PDF with references)
    64. Amateri u nauci Politika (Kulturni dodatak) 12th August 2023 (PDF with references)
    65. Gde su naši autoriteti u naukama Politika (Kulturni dodatak) 30th September 2023 (PDF with references)
    66. Manje popularizacije nauke Politika (Kulturni dodatak) 14th October 2023 (PDF with references)
    67. Razlikovanje naučnika od prodavaca u nauci Politika (Kulturni dodatak) 4th November 2023 (PDF with references)
    68. Zaostavština u nauci Politika (Kulturni dodatak) 25th November 2023 (PDF with references)
    69. Svi koji piju šampanjac žive duže? Politika (Kulturni dodatak) 13th January 2024 (PDF with references) (JPG)
    70. Kultura sastanaka Politika (Kulturni dodatak) 10th February 2024 (PDF) (JPG)
    71. Posao i prijateljstvo Politika (Kulturni dodatak) 2nd March 2024 (PDF)
    72. Kultura na ulici Politika (Kulturni dodatak) 16th March 2024 (PDF) (Kultura na ulici)
    73. Protiv statističke značajnosti Politika (Kulturni dodatak) 1st June 2024 (PDF)

    Internet publications:

    1. Is Science a one-way street? (PDF version)
    2. Artificial Intelligence with an “I don’t know” answer (PDF version)
    3. Criticism within Science (PDF version)
    4. How the Journal of Cheminformatics lost my published paper?
    5. Models with "don't know" predictions
    6. Genetic variations in prediction of inflammatory bowel disease occurrence
      D. Krstajic
      Letter to the Editor of the Journal of Digestive Diseases
    7. Klasifikacija živog sveta sa posebnim osvrtom na novu klasifikaciju gljiva (2008) (en. Classification of living matter with emphasis on classification of fungi) PDF
      B. Uzelac, D.Krstajić