Prospectus

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Design and Analysis of Biological Experiments

Course
2024-2025

Admission requirements

  • Linear Models

  • Recommended: Essentials of Mixed and Longitudinal Modelling

Description

A good study design is important because poorly designed studies will produce imprecise and biased results. Furthermore, an experiment with plants or animals that doesn't produce significant results is a waste of time, money and resources. From a statistical point of view, a statistical design addresses the choice of treatments and how to deal with disturbing factors and sources of random variation. The statistical principles underlying experimental designs can be summarized by randomization, replication and blocking. In this course, you will learn about the most common designs for biological and agricultural experiments and how to analyze them. Further, you will learn about criteria and strategies for choosing treatments and experimental designs.

Course Objectives

The students are able to:

  • describe the three principles of experimental design

  • identify the structural characteristics of common agricultural and biological experimental designs and propose adequate linear and linear mixed models for their analysis: completely randomized design, randomized complete block design, incomplete block design, Latin square design, split plot design

  • identify the explanatory characteristics of common agricultural and biological experimental designs and propose adequate models for their analysis: factorial, crossed, nested, use of control treatment, fractional factorial, response surface

  • define relevant treatment contrasts and corresponding standard errors as functions of experimental design and replication

  • choose and motivate a suitable experimental design for a particular situation

  • choose and motivate adequate linear (ANOVA) and linear mixed models corresponding to a particular situation, perform calculations and interpret results from given software output

  • make sample size and power calculations for simple designs

  • describe specifics of mixed models in balanced case: expected mean squares for common designs and corresponding F-tests for treatment differences, and standard errors and t-tests for treatment differences

  • describe specifics of mixed models in unbalanced case: use of REML, intra- and inter-block variation and recovery of inter block information

  • describe aspects of design and analysis of large field trials

  • present selected homework assignments in class

Timetable

In MyTimetable, you can find all course and programme schedules, allowing you to create your personal timetable. Activities for which you have enrolled via MyStudyMap will automatically appear in your timetable.

Additionally, you can easily link MyTimetable to a calendar app on your phone, and schedule changes will be automatically updated in your calendar. You can also choose to receive email notifications about schedule changes. You can enable notifications in Settings after logging in.

Questions? Watch the video, read the instructions, or contact the ISSC helpdesk.

Note: Joint Degree students from Leiden/Delft need to combine information from both the Leiden and Delft MyTimetables to see a complete schedule. This video explains how to do it.

Mode of Instruction

Lectures and discussion of exercises, homework and assignments.

Assessment method

Written exam, plus a limited number of mandatory group assignments and presentations thereof during the lecturing period, which will be graded. The final grade will consist of 1/3 x the average grade for the assignments + 2/3 x the grade for the written exam. For a pass the final grade should be at least 6 and both the average grade for the assignments and the grade for the written exam should be at least 5. In case one of the two grades is lower than 5, the final grade is the minimum of the two grades.

Reading list

Welham SJ, Gezan SA, Clark SJ, Mead A. Statistical Methods in Biology: Design and Analysis of Experiments and Regression. Chapman and Hall/CRC. 2014

Registration

As a student, you are responsible for enrolling on time through MyStudyMap.

In this short video, you can see step-by-step how to enrol for courses in MyStudyMap.
Extensive information about the operation of MyStudyMap can be found here.

There are two enrolment periods per year:

  • Enrolment for the fall opens in July

  • Enrolment for the spring opens in December

See this page for more information about deadlines and enrolling for courses and exams.

Note:

  • It is mandatory to enrol for all activities of a course that you are going to follow.

  • Your enrolment is only complete when you submit your course planning in the ‘Ready for enrolment’ tab by clicking ‘Send’.

  • Not being enrolled for an exam/resit means that you are not allowed to participate in the exam/resit.

Contact

Gerrit Gort

Remarks

Software
Starting from the 2024/2025 academic year, the Faculty of Science will use the software distribution platform Academic Software. Through this platform, you can access the software needed for specific courses in your studies. For some software, your laptop must meet certain system requirements, which will be specified with the software. It is important to install the software before the start of the course. More information about the laptop requirements can be found on the student website.