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*For academic and multiple registration discounts, please contact us before registering. contact us

This course has been developed for technical and supervisory personnel involved in all aspects of sensory and consumer research.


Fundamentals of Discrimination Testing

and Drivers of Liking®

May 23 - 25, 2023

The Royal Savoy Hotel & Spa | Lausanne, Switzerland


In-person attendance | $2,250 USD (€ 2150 approx.)

Virtual attendance | $1,875 USD (€ 1790 approx.)


  • Printed manuals of slides and exercises

  • 3-month free software trial of IFPrograms® Professional 

  • A printed copy of our book, Tools and Applications of Sensory and Consumer Science and PDF downloads of the following 2 books: Thurstonian Models: Categorical Decision Making in the Presence of Noise

The instructors for this course will be:


The Institute for Perception


The Institute for Perception

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The Institute for Perception

Tuesday, May 23  |  8:30 - 16:30 CET


  • The broad range of Thurstonian models: Triads and tetrads, dual pair, m-AFC, triangle, duo-trio, same-different, degree of difference, ap-plicability scoring, first-last choice, maxdiff, just-about-right scales, category scales, and ranking

  • Response-based analysis vs. Thurstonian models

  • Thurstonian models for discrimination testing: Variability, decision rules, d' values and variances

  • Detailed account of common difference testing methods: 2-AFC, duo-trio, triangle, tetrad

  • A better alternative to proportion detectors in the population

  • Why the tetrad is superior to the triangle and duo-trio methods

  • Power and sample sizes for difference testing methods

  • Consumer-relevant action standards and how to create them

  • Same-different vs. paired preference for consumer relevance

  • Risk and sample size when switching to the tetrad method

  • Building a successful internal sensory program


IFPrograms® Exercises

  • Ingredient supplier change: Texture of cookies using 2-AFC and triangle

  • Consumer preference without a sensory difference

  • Variability in proportion detector estimates

  • Estimating panel sample sizes as a function of method, power, allpha, and size of the difference

  • Same-different method to establish consumer relevance (δR)

  • Linking internal panel and consumer sensitivities

  • Switching from the triangle to the tetrad method

  • Internal sensory program development at a major food company

Wednesday, May 24  |  8:30 - 16:30 CET


  • Why liking and utility are forms of similarity

  • Why link consumer and sensory data?

  • The sensory space in contrast to the Drivers of Liking space

  • How to plan a category appraisal (IFPrograms® exercises)

    • Product selection using graph theory

    • Method comparison to generate sample presentation orders

    • Multiple day effect, complete vs. incomplete block designs

  • First mapping option for ingredient change project

    • Factor analysis and its limitations

    • Assumptions and potential limitations of the approach

Thursday, May 25  |  8:30 - 16:30 CET


  • Introduction to Landscape Segmentation Analysis® (LSA): Liking as a form of similarity (IFPrograms® exercises)

    • Successive analytical steps

    • Unfolding—combining models from Thurstone and Coombs

  • Applications of LSA principles to ingredient change project (IFPrograms® exercises)

    • Creating the product and consumer ideal point space

    • Studying consumer segmentation

    • Regressing sensory and analytical information to uncover the driv-ers of liking

  • Limitations of internal and external preference mapping that do not account for perceptual variance and individual ideal points

  • Application of LSA to 27 real-world category appraisals

  • Using the Drivers of Liking Space (IFPrograms® exercises)

    • Creating optimal product sensory profiles and portfolios

      • Maximizing consumer satisfaction (absence of competition)

      • Best strategy to avoid cannibalization

      • Maximizing first choice against competition

      • Using machine learning to characterize uncovered consumer subgroups

  • Extending the use of an LSA space: New product predicted perfor-mance (IFPrograms® exercises)

    • Determine the spatial location of new products using their sensory and analytical profiles

    • LSA as a computer-aided design tool: Predict consumer acceptability using ideal points without new consumer testing

  • Novel applications of LSA in the real world

  • Course conclusions


Please enter your information below to register for this course. Those registering 2 or more attendees from the same company are eligible for a 10% discount on the 2nd registration. Please contact us before registering if you are eligible for a discounted rate. 

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