The Matilda effect is the common bias against acknowledging the contribution of woman scientists in research, whose work is often attributed to their male colleagues. This effect was first described by 19th century suffragist and abolitionist Matilda Joslyn Gage in her essay "Woman as Inventor", and coined in 1993 by science historian Margaret W. Rossiter.
The Matilda effect is related to the Matthew effect, since eminent scientists will often get more credit than a comparatively unknown researcher, even if their work is shared or similar.
Rossiter provides several examples of this effect: Trotula, an Italian physician (11th–12th centuries), wrote books which were attributed to male authors after her death, and hostility toward women as teachers and healers led to denial of her very existence. Twentieth-century cases illustrating the Matilda effect include those of Nettie Stevens, Maria Skłodowska Curie (she was included in the 1903 Nobel Prize in physics only on the insistence of a committee member—Swedish mathematician Magnus Goesta Mittag-Leffler—and of her husband Pierre Curie), Lise Meitner, Marietta Blau, Rosalind Franklin, and Jocelyn Bell Burnell.
From an analysis of more than a thousand research publications from the years 1991-2005, it was shown that male scientists more often cite the publications of male authors than of female authors. In 2012, two female researchers from Radboud University Nijmegen showed that in the Netherlands the sex of professorship candidates influences the evaluation made of them. Similar cases are described in an Italian study  corroborated further by American and Spanish studies.
Swiss researchers have indicated that mass media ask male scientists more often to contribute on shows than they do their female fellow scientists.
US male scientists still receive more recognition and awards compared with women scientists, despite similar achievements. This difference is diminishing. It was more pronounced in the 1990s than in the 2000s.
Famous examples of women in history of science include:
- Trotula - Italian medic of the living 11th - 12th century, author of works that after her death started to be published and ascribed to male authors. To further support male authorship, her very existence was questioned.
- Rosalind Franklin - now recognized as one of the main contributors to the discovery of DNA structure. At the time of the discovery by Francis Crick and James Dewey Watson her work was not properly given credit.
- Gerty Cori - worked for years as her husband's assistant despite having equal qualification as him for professor position.
- Harriet Zuckerman - as a result of the Matilda effect, Zuckerman is also credited by husband Robert K. Merton as the co-author of the Matthew effect.
- Mary Whiton Calkins - Harvard University discovered that stimuli that were paired with other vivid stimuli would be recalled more easily. She also discovered that duration of exposure led to better recall. These findings, along with her paired-associations method would later be used by Georg Elias Müller and Edward B. Titchener without any credit given to Calkins.
- Marthe Gautier - recently revealed example of Matilda effect. Gautier is now recognized for her important role in the discovery of the chromosomal abnormality that causes Down syndrome while it has been attributed exclusively to Jérôme Lejeune.
- Nettie Stevens - her crucial studies of mealworms revealed that an organism’s sex is determined by its chromosomes instead of environmental or other factors for the first time. Stevens greatly influenced the scientific community’s transition to this new line of inquiry: chromosomal sex determination. However, Thomas Hunt Morgan, a distinguished geneticist at the time, is generally credited with this discovery. Despite her extensive work in the field of genetics, Stevens’ contributions to Morgan’s work are often disregarded.
- Programmers of ENIAC - several women made substantial contributions to the project, including Adele Goldstine, Kay McNulty, Betty Jennings, Betty Snyder, Marlyn Wescoff, Fran Bilas and Ruth Lichterman, but histories of ENIAC have typically not addressed these contributions, and have at times focused on hardware accomplishments rather than software accomplishments. More information can be found in Jennifer S. Light's essay, "When Computers Were Women", and in a 2014 documentary on the ENIAC programmers project.
Examples of male scientists favoured over women scientists by Nobel Prize:
- In 1934, the Nobel Prize in physiology or medicine was awarded to George Whipple, George Richards Minot and William P. Murphy. They felt their female coworker Frieda Robscheit-Robbins was excluded on grounds of her sex and shared the prize with her. She was co-author of almost all publications by Whipple.
- In 1944, the Nobel Prize in Physics was given to Otto Hahn as the sole recipient. Lise Meitner worked with Hahn and laid the theoretical foundations for nuclear fission and coined the term "nuclear fission." Meitner was not recognized by the Nobel Committee, partly due to her gender and partly due to her persecuted Jewish identity in Nazi Germany. She was affected by the Law for the Restoration of the Professional Civil Service, which prohibited Jews from holding government-related positions, including in research. Initially, her Austrian citizenship shielded her from persecution, but she fled Germany after Hitler's annexation of Austria in 1938.
- In 1950, Cecil Powell received the Nobel Prize in Physics for his development of the photographic method of studying nuclear processes and for the resulting discovery of the pion (pi-meson). Marietta Blau did pioneering work in this field. Erwin Schrödinger had nominated her for the prize along with Hertha Wambacher, but both were excluded.
- In 1956, two American physicists Tsung-Dao Lee and Chen Ning Yang, predicted the violation of the parity law in weak interactions and suggested a possible experiment to verify it. In 1957, Chien-Shiung Wu performed the necessary experiment in collaboration with National Institute of Standards and Technology and showed the parity violation in the case of beta decay. The Nobel Prize in Physics in 1957 was awarded to the male physicists and Wu was omitted. She received the Wolf Prize in 1987 in recognition for her work.
- In 1958, Joshua Lederberg shared a Nobel Prize in Physiology or Medicine with George Beadle and Edward Tatum. Microbiologists Joshua Lederberg and his wife Esther Lederberg, along with Beadle and Tatum, developed replica plating, a method of transferring bacterial colonies from one petri dish to another, which is vital to current understanding of antibiotic resistance. However, Esther Lederberg was not recognized for her vital work on this research project; her contribution was paramount to the successful implementation of the theory. Furthermore, she did not receive recognition for her discovery of the lambda phage or for her studies on the F fertility factor that created a foundation for future genetic and bacterial research.
- In 1974 Jocelyn Bell Burnell discovered the first radio pulsars. For this discovery the Nobel Prize was awarded to her supervisor Antony Hewish and Martin Ryle, citing Ryle and Hewish for their pioneering work in radio-astrophysics, with particular mention of Ryle's work on aperture-synthesis technique, and Hewish's decisive role in the discovery of pulsars. Burnell was left out. Being a PhD student at the time of the discovery she felt the intellectual effort was done mostly by her supervisor but her omission was disproved by several prominent astronomers including Sir Fred Hoyle. Dr. Iosif Shklovsky, recipient of the 1972 Bruce Medal, had sought out Bell at the 1970 International Astronomical Union's General Assembly, to tell her: "Miss Bell, you have made the greatest astronomical discovery of the twentieth century."
Ben Barres, who is a neurobiologist at Stanford and has transitioned from female to male, has talked about his experiences of his scientific achievements being perceived differently depending on gender.
- Rossiter Margaret W. (1993), "The Matthew/Matilda Effect in Science", Social Studies of Science, London: Sage Publ., 23: 325–341, doi:10.1177/030631293023002004, ISSN 0306-3127
- Resnick, Brian (2016-07-07). "Nettie Stevens discovered XY sex chromosomes. She didn't get credit because she had two X's.". Vox. Retrieved 2016-07-07.
- Silvia Knobloch-Westerwick; Carroll J. Glynn (2013), "The Matilda Effect—Role Congruity Effects on Scholarly Communication A Citation Analysis of Communication Research and Journal of Communication Articles", Communication Research, Sage Publ., 40 (1): 3–26, doi:10.1177/0093650211418339
- Marieke van den Brink; Yvonne Benschop, "Gender practices in the construction of academic excellence: Sheep with five legs", Organization, 19 (4): 507–524, doi:10.1177/1350508411414293
- Andrea Cerroni; Zenia Simonella, "Ethos and symbolic violence among women of science: An empirical study", Social Science Information, 51 (2): 165–182, doi:10.1177/0539018412437102
- Peter Hegarty; Zoe Walton, "The Consequences of Predicting Scientific Impact in Psychology Using Journal Impact Factors", Perspectives on Psychological Science, 7 (1): 72–78, doi:10.1177/1745691611429356
- María Luisa Jiménez-Rodrigo1; Emilia Martínez-Morante; María del Mar García-Calvente; Carlos Álvarez-Dardet (2008), "Through gender parity in scientific publications", Journal of Epidemiology & Community Health, doi:10.1136/jech.2008.074294
- Fabienne Crettaz von Roten (2011), "Gender Differences in Scientists' Public Outreach and Engagement Activities", Science Communication, 33 (1): 52–75, doi:10.1177/1075547010378658
- Anne E. Lincoln; Stephanie Pincus; Janet Bandows Koster; Phoebe S. Leboy (2012), "The Matilda Effect in science: Awards and prizes in the US, 1990s and 2000s", Social Studies of Science, 42 (2): 307–320, doi:10.1177/0306312711435830
- Hagen, Joel (1996). Doing Biology. Glenview, IL: Harper Collins. pp. 37–46.
- "6 Women Scientists Who Were Snubbed Due to Sexism". Retrieved 2015-10-04.
- "Nettie Maria Stevens (1861-1912) | The Embryo Project Encyclopedia". embryo.asu.edu. Retrieved 2015-10-04.
- Light, Jennifer S. (1999). "When Computers Were Women" (PDF). Technology and Culture. 40 (3): 455–483.
- "ScienceWeek". 2013-04-14. Archived from the original on April 14, 2013. Retrieved 2015-10-10.
- "CensorshipIndex". www.esthermlederberg.com. Retrieved 2015-10-10.
- "Esther Lederberg, pioneer in genetics, dies at 83". Stanford University. Retrieved 2015-10-10.
- Shankar Vedantam, (13 July 2006). Male Scientist Writes of Life as Female Scientist: Biologist Who Underwent Sex Change Describes Biases Against Women. Washington Post