What makes an expert?

• Novice to competent practitioner via building mental model.
• Novices don’t have a good mental model
• Competent practitioners have a good-enough mental model

Exercise: What is an expert?

• Name someone that you think is an expert (doesn’t matter what they’re an expert in). As an expert, what makes them special or different from other people?

OR

• What is something that you’re an expert in? How does your experience when you’re acting as an expert differ from when you’re not an expert?

This discussion should take about 5 minutes.

What makes an expert

Experts have more connections between pieces of knowledge – it’s not just that they know more facts. Experts can

• see connections that others can’t
• see a single problem in different ways (fluid representations)
  • e.g. character vectors vs strings
  • e.g. numerical vs logical array indexing
• jump from problem to solution without ‘showing their working’
  • Competent practitioner would reason A, therefore B, etc.

Expertise and teaching

• As an expert, conclusions which seem obvious to you will likely not be to your learners.
• Two ways of thinking about a problem may be interchangeable to you (but not to a novice!)
• Therefore it’s important to explain what you’re doing step-by-step
  • e.g. switching between relative and absolute paths in Bash
  • This is particularly important when diagnosing errors: be explicit about the process even if it seems trivial to you

Exercise: Fluid representations

In the shared document, give at least one example of a fluid representation that you use in your own work. If you can, also give an example of a fluid representation that might occur in a Carpentry lesson.

This discussion should take about 5 minutes.

Expert blind spot

• Experts are often so familiar with their subject they can’t image not seeing the world from a non-expert perspective
• This is why some excellent researchers make poor lecturers
• Can be overcome with training
  • Identify potential blindspots
  • View the problem from the learner’s perspective

Dismissive language

Just

Gives learners the very clear signal that the instructor thinks their problem is trivial and that they therefore must be stupid.

With practice we can avoid this type of demotivating language and replace it with more positive word choices.

Exercise: Changing your language

• What other words or phrases can have the effect of demotivating learners?

• What alternatives can we use to express this meaning in a positive and motivational way?

• In the shared document, make a list of demotivating words/phrases and alternatives.

This discussion should take about 5 minutes.

What questions do people have?

• Asking this instead of ‘Does anyone have any questions?’ indicates that you’re expecting questions, and that this is normal.
• ‘Any questions?’ can create the impression you hope there won’t be any.

You are not your learners

• Most scientists’ primary goal is not to program, but to do scientific research.
• We therefore have to make sure that everything we teach is useful right away, and conversely that we don’t teach anything just because it’s “fundamental”.
• Believing that something will be hard to learn is a self-fulfilling prophecy.
  • It’s important not to say that something is easy.
  • If someone who has been told that tries it, and it doesn’t work, they are more likely to become discouraged.

Importance of practice

• Use formative assessments frequently to help tailor your teaching to your learners
  • Find out about your learners’ goals and motivations
  • Overcome your expert blindspot

Key points

• Experts face challenges when teaching due to expert blindspot
• Expert blindspot is knowing something so well it seems easy when it isn’t
• Can overcome expert blindspot with practice