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Project 1
For this project, you will design and build a web-based behavioral experiment.
Each experiment should follow this basic structure:
- Consent - Use this text
- Instructions - Provide the participant instructions on what they need to do
- Trials/Conditions
- Debrief - Thank the participant and give them a brief explanation about the goal(s) of the experiment they just completed.
The MVP (explained below) should be a between-subjects design, meaning each participant is only exposed to one level of the independent variable.
Demo
Semantic Priming in Lexical Decision
(This experiment has been paired down from 36 trials to 6 for the purposes of expediting the demo.)
MVP and PLUS versions
When designing your experiment, it’s important to start simple and then consider how you might expand if you have extra time.
With this in mind, your proposal will cover two versions of your experiment - a MVP (Minimum Viable Product and a PLUS (Possible Later Upgrades / Stretch).
The MVP is the simplest working version of your experiment. It should:
- Address your research question at a basic level
- Use a small set of conditions/stimuli
- Be something you feel confident you can finish within the time available
Example MVP (Stroop Task):
- Show 2 conditions: congruent vs. incongruent
- Record reaction time and accuracy
Your PLUS version can include nice-to-have features or extra layers of complexity you could add if your MVP is working and you have time. These might be:
- More conditions (e.g., add neutral trials)
- More stimuli (e.g., longer word lists, images instead of text)
- More advanced design (e.g., blocks of trials, practice vs. test phases)
- More detailed feedback or data collection
Example PLUS (Stroop Task):
- Add a neutral condition (e.g., “###” in colored font)
- Track trial-by-trial feedback (Correct/Incorrect)
- Randomize trial blocks with instructions between them
Logistics
You will complete this project with a classmate, but each student will be responsible for and graded on their own unique submission.
Every student will be graded primarily on their MVP.
Time permitting, students are encouraged (but not required) to complete a second version of their experiment that includes some of their PLUS features.
Proposal
➡️ Example Project Proposal...
You are welcome to make a copy of this proposal and use it as your template, swapping in the appropriate details for your project
Your document must addresses the following points:
- Experiment title and summary
- Research question: What psychological question are you hoping to answer with your experiment?
- Hypothesis: What do you expect to happen?
- Independent Variable(s):
- What condition(s) will you manipulate?
- List all levels and give the operational definition.
- Limit your IV to 2-3 levels for the MVP version.
- Dependent Variable(s):
- What outcome(s) will you measure?
- How will you compute the outcomes? (e.g., median response time of correct trials (ms); accuracy (percent correct), etc.).
- Limit to 1-2 DVs for the MVP version.
- Experiment Design:
- Describe how the experiment will work - what participants will see/do.
- How many blocks/trails will there be?
- What stimuli will you use? Be specific.
- What will the different screens look like and what exactly will they say? Feel free to include sketches.
- Misc.
- Will there be a fixation?
- How long will the stimulus be presented (briefly or until response)?
- Will the response window be limited?
- Will they see feedback?
- Will there be an inter-trial interval (ITI) between stimuli and for how long?
- None of the above are required - apply them as they make sense for your experiment (some may be appropriate add-ons for your "PLUS" version).
- jsPsych Plugins: Which jsPsych plugins will you use (e.g., html-keyboard-response, image-keyboard-response, survey-likert)?
Your proposal will be graded based on thoroughness and attention to detail. Imagine your response as a set of instructions you could share with another researcher that would be in charge of implementing your experiment - you must provide as many details as would be necessary for them to fully execute your plan.
Example Project Ideas
Example 1. Stroop Effect
- Research Question: Are people slower and less accurate when the meaning of a word conflicts with its color?
- Experiment Design:
- Show words like “RED” or “BLUE” in colored font.
- Participants press keys for the font color (not the word meaning).
- IV: Congruent vs. incongruent trials.
- DV: Reaction time, error rate.
- Prediction: Slower RTs and more errors on incongruent trials.
Example 2. Reaction Time and Distraction
- Research Question: Does background distraction slow down reaction times?
- Experiment Design:
- Participants press a key as quickly as possible when a circle appears on the screen.
- In half the trials, the circle appears on a blank background; in the other half, distracting images or patterns are shown.
- IV: Background condition — whether the target circle appears with a blank background or with distracting images/patterns.
- DV: Reaction time.
- Prediction: Reaction times will be slower when distractions are present.
Example 3. Working Memory Load
- Research Question: Does increasing the number of items in memory reduce accuracy on a recognition task?
- Experiment Design:
- Show participants a short sequence of letters (2, 4, or 6 letters).
- Then show a single probe letter, and participants respond “yes” if it was in the sequence, “no” if not.
- IV: Set size (2, 4, 6).
- DV: Accuracy, reaction time.
- Prediction: Accuracy will decline and RTs will increase as set size increases.
Example 4. Priming and Word Recognition
- Research Question: Does a prime word influence how quickly a related target word is recognized?
- Experiment Design:
- Show a prime word (e.g., “doctor”), followed quickly by a target word (e.g., “nurse” or “chair”).
- Participants decide if the target is a real word or a non-word.
- IV: Prime type (related vs. unrelated).
- DV: Reaction time to classify the target.
- Prediction: RTs will be faster when the prime is related to the target.
Example 5. Visual Search
- Research Question: Is it harder to find a target when distractors are more similar to it?
- Experiment Design:
- Participants look for a red circle among distractors.
- Distractors are either very different (blue squares) or very similar (red squares).
- IV: Distractor similarity (different vs. similar).
- DV: Reaction time, accuracy.
- Prediction: RTs will be slower when distractors are similar to the target.
Research Question Inspiration
If you’re having a hard time coming up with a research question, you may pick from one of the following:
Memory
- Do people remember images better than words?
- Does repetition improve memory recall?
- Does the order of presented information affect recall?
Attention & Perception
- Does the presence of a time limit affect accuracy?
- Does multitasking slow down response times?
- Does the color of a stimulus influence how quickly people notice it?
- Does the location of a stimulus on the screen affect how quickly people respond?
- Do people detect changes in faces more quickly than changes in objects?
Learning & Practice
- Does practicing a task improve performance over repeated trials?
- Does feedback (correct/incorrect) affect later performance?
Language Processing
- Do people respond faster to familiar words compared to unfamiliar ones?
- Are people faster at recognizing positive words than negative words?
Decision-Making
- Does mood influence decision-making speed?
- Does making a choice between two options affect confidence in that choice?
- Do people make riskier choices when potential rewards are larger?