Base-rate fallacy is defined as an error in reasoning which someone commits when he or she makes a conclusion that fails to account for an earlier premise, usually a probability or base rate. In other words, it is a cognitive error which occurs when a person reaches a judgment of an outcome without considering prior knowledge of the probability that it will occur (Kassin et al. 124). Instead, he or she focuses on other information that is not relevant.
The situation in which I committed the error is when I made a conclusion on an advertisement that Biotin is able to return fingernails to a healthy thickness. It has been said that nails are the barometer of a person’s overall health. That is certainly true even when the condition of a person is getting older. The fingernails go through changes over time as the body ages. Also, some internal factors such as diseases, nutritional deficiencies or external factors such as ultraviolet rays can cause cracking of nails. Over time, fingernails may experience changes in texture, thickness, growth rate, shape or color. Thinning of fingernails is one of the effects of aging that causes them to crack and chip. So, when I saw the ad advertising Biotin, I decided to buy a couple of bottles. After some time, I stopped taking the pills after realizing there was no any improvement on my hands. In addition to that, I read in a review of nutrition research explaining that there are no virtual controlled, double-blind, studies that have shown its effectiveness. Despite the lack of research evidence that biotin works, a medical doctor will tell me to take biotin, every few years and I will obediently go and buy a bottle or two.
The error I committed is related to the definition of a base-rate fallacy because I was told to use Biotin by a single medical doctor, who I respect and love. This made me reach a conclusion without considering the prior knowledge provided by the review of nutrition research that biotin is not effective. In fact, the reviewed nutrition research showed that cracking and chipping of fingernails have multiple causes and taking biotin supplements may interfere with the process of healthier and stronger growth. Therefore, I was insensitive to research evidence and failed to account on hundreds of subjects (“base-rate”) showing that taking Biotin for a healthy thickness of fingernails is a waste of money and time.
I was able to connect my faulty thinking when I came to read several articles on nutrition showing the need of not taking biotin to make fingernails stronger. All these articles I read were showing that the vitamin B contained in Biotin is plenty in food such as salmon, eggs, and almond. Hence, Biotin is ineffective.
I realized my focus was on other information that was not relevant. Therefore, if I were to find myself in the same situation, a product of nutrition supplement being recommended to me, I will not judge an outcome that occurs without an earlier knowledge of the probability that it will occur. But, I would first make sure that I have read the research finding before buying the product.
The definition came from page 124 of Social Psychology, 9th edition written by Kassin, Fein, and Markus. The book is three-hole punch version.
Work Cited
Kassin, Saul, et al. Social Psychology [Australia and New Zealand 9th edition]. Cengage Learning Australia, 2015.
