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OSAC Lexicon

The OSAC Lexicon is a compendium of forensic science terms and definitions. This terminology tool was created to help bring consistency and understanding to the way terms are used by the various forensic science. Use of the OSAC Lexicon does not replace the need to reference the original published source.

The terms and definitions in the OSAC Lexicon come from the published literature, including documentary standards and technical reports. It is continually updated with the latest work from OSAC units, as well as terms from newly published documentary standards and standards elevated to the OSAC Registry.

Gradually terms are evaluated and harmonized by the OSAC to a single term. This process results in an OSAC Preferred Term. An OSAC Preferred Term is a term, along with its definition, that has undergone review and evaluation by the FSSB Terminology Task Group and has been approved by the FSSB. The FSSB recommends that subcommittees use OSAC Preferred Terms when drafting standards.

The OSAC Lexicon should be the primary resource for terminology and used when drafting and editing forensic science standards and other OSAC work products

Displaying 1151 - 1200 of 3597
Searches term, definition, and source for any of these keywords.
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Evidence Search Dog

A canine trained to locate and indicate items in question by means of detecting a trained odor/ human scent.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link
evidentiary data

Data generated from an evidentiary sample and not from a reference sample.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 139 Reporting DNA Conclusions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link
Evidentiary Data

Data derived from biological specimens of unknown source.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 040 Standard for Forensic DNA Interpretation and Comparison Protocols. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link
evidentiary sample

Biological sample recovered from a crime scene or collected from persons or objects associated with a crime.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 139 Reporting DNA Conclusions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link
examination

part of the forensic process consisting of the recovery and analysis of items, and the interpretation of observations obtained from the analysis of items


Note 1 to entry: See Annex A for a flowchart of the forensic process.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ISO 21043-1:2025 Forensic sciences — Part 1: Vocabulary. International Organization for Standardization BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva, Switzerland, 2025. Source link
Reprinted, with permission, from ISO, copyright International Organization for Standardization, 1214 Vernier, Geneva, Switzerland. A copy of the complete standard may be purchased from ISO, https://www.iso.org/store.html
examination

The process of observing, searching, detecting, recording, prioritizing, collecting, analyzing, measuring, comparing, and/or interpreting.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Standard 207 Standard for Collection and Preservation of Document Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2026. Source link
examination

The process of observing, searching, detecting, recording, prioritizing, collecting, analyzing, measuring, comparing, and/or interpreting.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Technical Report 071 Forensic Document Examination: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
examination (modified)

part of the forensic toxicology process consisting of the analysis of specimen(s) and the interpretation of observations from the analysis

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB Technical Report 208, Forensic Toxicology: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
Examination Quality Photograph

A photograph that is scalable and captures a sufficient level of detail for conducting a forensic footwear or tire examination.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB Technical Report 097, Terminology Used for Forensic Footwear and Tire Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2026. Source link
examination strategy

choice of method(s) and sequence of methods for the examination 


Note 1 to entry: An examination strategy is based in part on relevant case questions and background information.
Note 2 to entry: An examination strategy can be applied to the examination of a scene, the examination of items or sequential multi-discipline examination of items.
 

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ISO 21043-1:2025 Forensic sciences — Part 1: Vocabulary. International Organization for Standardization BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva, Switzerland, 2025. Source link
Reprinted, with permission, from ISO, copyright International Organization for Standardization, 1214 Vernier, Geneva, Switzerland. A copy of the complete standard may be purchased from ISO, https://www.iso.org/store.html
Examiner
in facial identification, an individual whose role it is to perform a facial examination.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org
examiner (friction ridge, competent friction ridge examiner

An individual authorized to conduct independent friction ridge examinations for the forensic service provider by observing and interpreting data, making decisions, forming conclusions and opinions, issuing reports and/or providing testimony. Use of the term “examiner” in this document refers to a “competent friction ridge examiner” and not a “trainee.”

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 168 Standard for Testimony Monitoring in Friction Ridge Examination. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link
Examiner (friction ridge)

An individual authorized to conduct independent friction ridge examinations for the forensic service provider by observing and interpreting data, making decisions, forming conclusions and opinions, issuing reports and/or providing testimony. Use of the term “examiner” in these documents refers to a “competent friction ridge examiner” and not a “trainee.”

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 145 Standard for Consultation During Friction Ridge Examination. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO
, 2023. Source link
examiner (friction ridge)

An individual who has successfully completed their FSP’s training program, and is authorized to conduct independent friction ridge examinations for the FSP by observing and interpreting data, making decisions, forming conclusions and opinions, issuing reports, and/or providing testimony. 

NOTE Use of the term “examiner” in these documents refers to a “friction ridge examiner” and not a “trainee.”

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Best Practice Recommendation 183 Best Practice Recommendation for Limited Friction Ridge Examinations. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2026. Source link
examiner (friction ridge)

An individual authorized to conduct independent friction ridge examinations for the FSP by observing and interpreting data, making decisions, forming conclusions and opinions, issuing reports and/or providing testimony. Use of the phrase examiner in these documents refers to a “competent friction ridge examiner” and not a “trainee.”

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Standard 013 Standard for Friction Ridge Examination Conclusions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, COAAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
examiner (friction ridge) ‐ (compare to trainee)

An individual who has successfully completed their FSP’s training program, and is authorized to conduct independent friction ridge examinations for the FSP by observing and interpreting data, making decisions, forming conclusions and opinions, issuing reports and/or providing testimony. Use of the term “examiner” in these documents refers to a “friction ridge examiner” and not a “trainee,” refer to those definitions for further clarification.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 143 Standard for Technical Review in Friction Ridge Examination. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link
examiner (friction ridge) – (compare to trainee)

An individual who has successfully completed their FSP’s training program, and is authorized to conduct independent friction ridge examinations for the FSP by observing and interpreting data, making decisions, forming conclusions and opinions, issuing reports and/or providing testimony. Use of the term “examiner” in these documents refers to a “friction ridge examiner” and not a “trainee.” Refer to those definitions for further clarification.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 015 Standard for Examining Friction Ridge Impressions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link
examiner (friction ridge) (compare to competent friction ridge examiner)

An individual authorized to conduct independent friction ridge examinations for the forensic service provider by observing and interpreting data, making decisions, forming conclusions and opinions, issuing reports and/or providing testimony. Use of the term “examiner” in these documents refers to a “competent friction ridge examiner” and not a “trainee.”

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 014 Standard for Friction Ridge Examination Training Program. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link
Exchange Schema

Although NIEM contains thousands of elements it does not contain everything needed inan XML exchange. It contains the most common building blocks. In addition,implementers can define, in other exchange schemas, user-defined elements from theimplementers domain.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link
excitation

Elevation of the energy levels of atoms, molecules, or ions to higher energy levels. (CIE S 017/E:2011 ILV)

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Technical Report 071 Forensic Document Examination: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
Excitation filter
a filter used in fluorescence microscopy that transmits specific bands or wavelengths of energy capable of inducing visible fluorescence in various substrates.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org
exclusion

The known footwear or tire exhibits differences in class characteristics or distinguishing characteristics that indicate the footwear or tire did not make the questioned impression and thus is not part of the pool of potential sources for the questioned impression.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB Technical Report 097, Terminology Used for Forensic Footwear and Tire Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2026. Source link
Exclusion
OSAC Preferred

A result that compared items did not originate from the same source, are not the same substance, or do not share the same composition or classification, based on an exclusionary difference.

Also referenced in ASB 097, Terminology Used for Forensic Footwear and Tire Evidence.

Date Added to Lexicon
Committee Source
FSSB
exclusion elimination

The determination that there are sufficient characteristics in disagreement, with no significant limitations, to support an opinion that two or more items did not originate from the same source.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Technical Report 071 Forensic Document Examination: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
Exclusion Scent Check

A type of location search in which a scent match is not indicated by the canine thereby excluding an individual as the scent contributor.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link
Exclusion with Limitations
the result of a comparison between two hair samples in which the characteristics of the questioned hair differ from those present in the known hair sample, and therefore the donor of the known sample cannot be included as a possible source of the questioned hair. Discussion—This result is reached in a comparative hair examination when differences are noted in the macroscopic or microscopic characteristics between the questioned and known hairs; however, the differences are insufficient for an absolute exclusion of a person as a possible source. This could be due to the natural variation that occurs in hairs as a biological specimen, the effect that time or environment can have upon a hair, or the reference sample does not capture the complete variation of the individual's hair.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org
exclusion, exclusionary conclusion

A conclusion that eliminates an individual as a contributor of DNA obtained from an evidentiary sample based on the comparison of DNA data.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 139 Reporting DNA Conclusions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link
Exclusion/Elimination
the result of a comparison between two hair samples in which exclusionary differences are observed in the characteristics of the questioned hair that are not present in the known hair sample, and therefore the donor of the known sample can be excluded as a possible source of the questioned hair. Discussion—This result is reached in a comparative hair examination when exclusionary differences (for example, color, characteristics indicative of ancestry) are noted in the macroscopic or microscopic characteristics between the questioned and known hairs. In these circumstances, the source of the known hairs, as represented by the known sample, is eliminated as a possible source of the questioned hair.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org
exclusionary difference

A difference in one or more characteristics between compared items that is sufficient to determine that the compared items did not originate from the same source, are not the same source, or do not share the same composition or classification. 

NOTE What is sufficient depends on the performance and limitations of the method used on the material in question.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB Technical Report 097, Terminology Used for Forensic Footwear and Tire Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2026. Source link
Exclusionary Difference
OSAC Preferred

a difference in one or more characteristics between compared items that is sufficient to determine that the compared items did not originate from the same source, are not the same source, or do not share the same composition or classification.

Also referenced in ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science
ANSI/ASTM E1732 Discussion—What is sufficient depends on the performance and limitations of the method used on the material in question.

Date Added to Lexicon
Committee Source
FSSB
exculpatory evidence

Evidence that may be favorable to the accused, impeach the prosecution’s evidence, or mitigate the offense.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 154 Standard for Training on Testimony for Forensic Biology . AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO , 2024. Source link
Exemplar
a specimen of physical evidence of known origin.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org
Exemplar
An item of known origin used in footwear and tire examinations.
Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB TR 097, Terminology Used for Forensic Footwear and Tire Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2019. Source link
Exemplar

The friction ridge prints of an individual, associated with a known or claimed identity,and deliberately recorded electronically, by ink, or by another medium (also called 'known prints').

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/NIST-ITL 1-2011 Update:2015 Data Format for the Interchange of Fingerprint, Facial & Other Biometric Information. ANSI/National Institute of Standards and Technology, 2011. Source link
exemplar impression (synonym of exemplar or known and exemplar prints) exemplar or known (synonym of exemplar impression and exemplar prints) exemplar prints (synonym of exemplar impression and exemplar or known)

The deliberately recorded images or impressions from the friction ridge skin of an individual. 

NOTE Examples may include inked tenprints, inked palm prints, Livescan prints, powder and lift prints, casted/molded prints, or photographs of friction ridge skin.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ASB Technical Report 012, Technical Report on the Articulation of the Reasoning and Foundational Principles Behind Friction Ridge Examinations. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
exemplar impression exemplar or known exemplar prints

The deliberately recorded images or impressions from the friction ridge skin of an individual. 

NOTE Examples may include, but are not limited to, inked tenprints, inked palm prints, Livescan prints, powder and lift prints, casted/molded prints, or photographs of friction ridge skin.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Standard 013 Standard for Friction Ridge Examination Conclusions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
exemplar impression, exemplar or known exemplar prints

The deliberately recorded images or impressions from the friction ridge skin of an individual. NOTE Examples may include, but are not limited to, inked tenprints, inked palm prints, Livescan prints, powder and lift prints, casted/moulded prints, or photographs of friction ridge skin.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 015 Standard for Examining Friction Ridge Impressions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link
exemplar impression, exemplar or known exemplar prints

The deliberately recorded images or impressions from the friction ridge skin of an individual. NOTE Examples may include, but are not limited to, inked tenprints, inked palm prints, Livescan prints, powder and lift prints, casted/moulded prints, or photographs of friction ridge skin.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Best Practice Recommendation 166 Best Practice Recommendation for Comparison and Evaluation of Friction Ridge Impressions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link
exemplar impression, exemplar or known exemplar prints

The deliberately recorded images or impressions from the friction ridge skin of an individual. 

NOTE Examples may include, but are not limited to, inked tenprints, inked palm prints, Livescan prints, powder and lift prints, casted/moulded prints, or photographs of friction ridge skin.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Best Practice Recommendation 165 Best Practice Recommendation for Analysis of Friction Ridge Impressions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link
exemplar prints

The deliberate recorded images or impressions from the friction ridge skin of an individual.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 014 Standard for Friction Ridge Examination Training Program. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link
exemplars

Samples of handwriting, printed text, paper, ink, etc., known (or purported) to have been produced by a particular individual, machine, or manufacturer.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB Standard 207 Standard for Collection and Preservation of Document Evidence. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2026. Source link
exemplars

Samples of handwriting, printed text, paper, ink, etc., known (or purported) to have been produced by a particular individual, machine, or manufacturer.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Technical Report 071 Forensic Document Examination: Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2025. Source link
exigent circumstances

Circumstances that would cause a reasonable person to believe that relevant prompt action was necessary to prevent physical harm to persons or animals, the destruction of relevant evidence or some other consequence improperly frustrating legitimate law enforcement efforts.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 169 Standard for Clinical Veterinary Forensic Examination. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2024. Source link
Expanded Uncertainty (U)

Quantity defining an interval about a result of a measurement that may be expected to encompass a large fraction of the distribution of values that could reasonably be attributed to the measurand. DISCUSSION(1) The fraction may be regarded as the coverage probability or level of confidence of the interval. (2) To associate a specific level of confidence with the interval defined by the expanded uncertainty requires explicit or implicit assumptions regarding the probability distribution characterized by the measurement result and its combined standard uncertainty. The level of confidence that may be attributed to this interval can be known only to the extent to which such assumptions can be justified. (3) An expanded uncertainty U is calculated from a combined standard uncertainty uc and coverage factor k using: U =k X uc.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
Working Group 1 of the Joint Committee for Guides in Metrology (JCGM/WG 1), JCGM 100:2008 GUM 1995, Evaluation of measurement data Guide to the expression of uncertainty in measurement. BIPM, Pavillon de Breteuil F-92312 Sevres Cedex, France, 2008. Source link
Expanded Uncertainty, U
quantity defining an interval about a result of a measurement that may be expected to encompass a large fraction of the distribution of values that could reasonably be attributed to the measurand. Discussion—(1) The fraction may be regarded as the coverage probability or level of confidence of the interval. (2) To associate a specific level of confidence with the interval defined by the expanded uncertainty requires explicit or implicit assumptions regarding the probability distribution characterized by the measurement result and its combined standard uncertainty. The level of confidence that may be attributed to this interval can be known only to the extent to which such assumptions can be justified. (3) An expanded uncertainty, U, is calculated from a combined standard uncertainty, uc, and coverage factor, k, using: U=k×uc.
Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASTM E1732 Standard Terminology Relating to Forensic Science. ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428, 2025. Source link
Reprinted, with permission, from ASTM E1732 Standard Terminology Relating to Forensic Science, copyright ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. A copy of the complete standard is available from ASTM International, https://www.astm.org
expectation value (e-value)

The number of distinct alignments expected by chance; the default sorting metric in BLAST search results.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ANSI/ASB 180 Standard for the Selection and Evaluation of GenBank® Results for Taxonomic Assignment of Wildlife . AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO , 2024. Source link
Experimental Bias

Anyone testing any idea has a strong expectation that leads to an influence about the outcome.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link
Expert

A person displaying special skill and knowledge in a given area derived from training, education, or experience.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link
expert system

A software program or set of software programs that interprets the data generated from a DNA analysis instrument platform in accordance with laboratory defined quality assurance rules and accurately identifies the data that does and does not satisfy such rules.

Date Added to Lexicon
Standard Source (Designation Number Title of Standard. Publisher, Place, Year.)
ASB Standard 091 Standard for Training in Analysis of Forensic Short Tandem Repeat (STR) DNA Data. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO, 2026. Source link
Expert Testimony

The testimony made by a qualified person about a scientific, technical, or professional issue. An expert is often called upon to testify due to his/her familiarity with the subject or special training in the field.

Date Added to Lexicon
Technical Report/Other Source (Author, Title of report. Publisher, Year.)
ANSI/Academy Standards Board (ASB), Crime Scene/Death Investigation - Dogs and Sensors - Terms and Definitions. AAFS Academy Standards Board (ASB), 410 North 21st Street, Colorado Springs, CO 80904, 2017. Source link
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