False Rejection


False rejection in technology refers to the incorrect denial of access or system functionality to an authorized person due to the failure of a biometric system or password-based security system. Essentially, it mistakenly identifies legitimate users as unauthorized. This results in legitimate users being unable to access the system or service.


The phonetics for the keyword “False Rejection” is: fɔːls rɪˈdʒɛkʃən

Key Takeaways

1. Definition: False Rejection, also known as a Type I error, occurs when a system mistakenly rejects an authentic user or accurately presented identification. This typically happens in identity verification systems like biometric devices, where the system incorrectly denies access to an authorized user.

2. Implications: A high False Rejection Rate (FRR) can be detrimental to a user’s experience, causing frustration and dissatisfaction. It reduces the system’s usability and efficiency as legitimate users might face unnecessary complications while accessing the system.

3. Mitigation: To minimize the False Rejection Rate, the system thresholds can be adjusted. However, this may increase the False Acceptance Rate (FAR), where unauthorized users are granted access, thus compromising security. Therefore, it is crucial to find a balanced threshold that minimizes both false rejections and false acceptances.


False Rejection is an important term in the realm of technology, particularly in the field of biometrics and authentication systems. It refers to a system’s incorrect refusal to authenticate a legitimate user, incorrectly identifying them as unauthorized. This can happen due to various reasons such as a change in the user’s biometric data or inaccuracies in the system’s recognition algorithms. False Rejection is significant because it directly impacts user experience and system reliability. If the false rejection rate is high, legitimate users will frequently face difficulties accessing the system, which can lead to frustration and reduced productivity. Thus, balancing the false rejection rate and security level is crucial in designing effective and user-friendly authentication systems.


False Rejection is an integral part of biometric and security systems, where it adds an extra layer of accuracy and integrity. Its primary purpose is to maximize the system’s security by minimizing the possibility of unauthorized access. False rejection refers to a certain error in security authentication wherein a system incorrectly rejects an access attempt by an authorized user. The error happens when the system falsely identifies the authorized users’ input as unmatching with the stored data, which might be a biometric trait like a fingerprint, iris pattern, or voice print.In addition to enhancing security, False Rejection also assists in maintaining the balance between user convenience and security level. A system with a high false rejection rate is considered more secure against false acceptance, but it can potentially disrupt routine operations and lead to user frustration. Therefore, an appropriate balance must be struck to ensure that the risk of false acceptance (allowing unauthorized users) is minimized, while not overly inhibiting authorized users’ access due to excessive false rejections. Optimization of this aspect greatly depends on the purpose and context of the particular system in which the biometric technology is used.


1. Biometric Authentication : A common usage of technology today is in biometric identification systems, such as fingerprint or facial recognition. For instance, when using your fingerprint to unlock your smartphone, a false rejection is when the system incorrectly rejects your fingerprint even though it’s the right one. This can happen due to factors like a partially captured fingerprint, placement angle, or if the finger is dirty or wet.2. Security Access Systems: Many businesses and organizations use card readers or key fobs as a method to control access to a building or specific area. If an authorized card or key fob is incorrectly rejected by the system, perhaps due to a misread or damage to the card, this is an instance of false rejection.3. Voice Recognition System: False rejection can also be experienced in systems that use voice recognition, like smart home assistants (Alexa, Google Home etc.). If you give a valid command that the system doesn’t recognize, possibly due to noise interference or slight changes in the person’s voice (such as a cold), this is another example of false rejection in real world technology.

Frequently Asked Questions(FAQ)

Q: What is False Rejection?A: False Rejection, often referred to as a Type I error, is an error in data reporting where a system incorrectly rejects an access attempt by an authorized user.Q: How does a False Rejection happen in biometric systems?A: In biometric systems, a False Rejection can occur when the system fails to identify the legitimate user due to various factors such as low quality of biometric inputs, changes in environmental conditions, or an injury to the user.Q: Is a False Rejection the same thing as a False Negative?A: In the context of authentication systems, False Rejection is similar to a False Negative. Both terms refer to scenarios where an acceptable data point or user is incorrectly denied.Q: Can False Rejections be completely avoided?A: While it’s virtually impossible to completely eliminate False Rejections, system designers strive to reduce the instances of False Rejections by fine-tuning the system’s sensitivity and implementing quality control measures.Q: How does a False Rejection impact user experience?A: Frequent False Rejections can be frustrating for users and may discourage them from using the system, as it prevents legitimate users from gaining access when needed.Q: What is the False Rejection Rate (FRR)?A: The False Rejection Rate is the likelihood that a system will mistakenly reject an authorized user. A high FRR means a system is overly strict, potentially denying access to legitimate users, while a low FRR may indicate the system is not secure enough.Q: How can I decrease the chances of a False Rejection happening?A: Ensuring clear and high-quality biometric inputs is one way to reduce the chances of a False Rejection. Regular system maintenance and updates also help improve its accuracy and reduce the occurrence of False Rejections.

Related Finance Terms

  • Biometric Authentication
  • False Acceptance Rate (FAR)
  • False Rejection Rate (FRR)
  • Error Trade-off
  • Biometric Security

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