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Meeting 5: predict, run, explain

These short activities connect the slides to the full workshop. They are ungraded. Use one as a five-minute class demonstration; use the other for a warm-up or independent practice. They replace part of the existing demonstration time.

Before every run, write one prediction. Afterward, record one row or screen that supports or contradicts it. Then make one change and explain the result without reading the code aloud.

1. A button returns an index.

Open the editable example. The editor supplies startup and output code so you can focus on the experiment. Expand Supplied setup and run lines to see those lines; downloaded JS includes them.

Predict: What response value will clicking Living produce?

Change and test: Reverse the choices array. Update the correct response to match, then inspect a correct and an incorrect click.

Inspect: Button responses are numeric indices starting at zero. The label, index, and scoring rule must stay aligned.

Write three short notes:

2. A click becomes a trajectory.

Open the editable example. The editor supplies startup and output code so you can focus on the experiment. Expand Supplied setup and run lines to see those lines; downloaded JS includes them.

Predict: Will a click without moving produce the same record as a curved movement?

Change and test: Move in a curve before clicking a response. Rerun with a nearly direct movement. Compare raw JSON and the trace.

Inspect: Use the decision row. Inspect x, y, t, event, and target rectangles. Coordinates belong to the experiment frame, not the whole slide.

Write three short notes:

Transfer to the workshop

For the semantic mouse task, identify the decision row and explain one target rectangle and one movement event. Then retrieve the exported result and check the final row. Distinguish this from merely reaching the last screen.

Diagnose one fault

The program compares a button response with the string “Living”.

Explain the cause and the smallest useful test. Do this before reading the check below.

Check your reasoning after an attempt

Example 1: With [“Living”, “Nonliving”], Living is index 0. After reversing the labels, Living is index 1. Comparing a button response with the string “Living” would fail.

Example 2: Both runs can end at the same button while containing different movement events. A 16 ms minimum interval is not a guaranteed sample rate. Pointer motion alone does not establish a cognitive conflict effect.

Fault: The button plugin records a numeric index. Compare with 0 or 1 for the active choices array, and check the mapping again after changing label order.

Keep a useful record

Download edited JS if you want to keep your change; a reset or refresh replaces it. For experiment examples, download JSON after the run. Source packs include HTML, the initializer, libraries, and assets: small-example source pack. These files are for learning; the workshop remains the core task.