5.1 False Positives and Negatives

Learning Goals

[Link to PlayPosit]

[Link to instructional video]

More details: [link to topic on SSS website]

After this lesson, students should

1. Understand that there is always the inevitability of a trade-off—for a given test, one can reduce the risk of false positives by increasing the risk of false negatives, and vice versa. You make this trade-off when you determine what the threshold is (e.g. convict someone if you’re 99% or 70% certain that they’re guilty).
2. Understand that whether false positive or negative is preferable depends on a human values judgement on the consequences of either: (e.g. “innocent people shouldn’t be in jail”) and risks (e.g dangerous people committing more crimes).

Definitions

• False Positive/Type I Errors

  A test yields a positive result, but in fact the condition is not present (e.g. your test says you have COVID, but you don’t)

• False Negative/Type II Errors

  A test yields a negative result, but in fact the condition is present. (e.g. your test says you don’t have COVID, but you do)

• Threshold

  The cut-off quantity chosen for an indicator variable to decide when a given instance will be supposed positive vs. negative.

Examples

• [item 1]

Common Misconceptions

• Mistaken quote

  Explanation.

Context

[Explanation of how the current topic into the larger context of the course by explaining how the previous topic(s) relate to the current topic and leaving cliffhangers for future topics where relevant throughout the lesson]

Before

X.X Lesson Name

Explanation.

• Itemized explanation.

After

X.X Lesson Name

Explanation.

• Itemized explanation.

Recommended Outline

Before Class

• [Any essential logistical things that need to be done for this class]
• Prepare a seating chart.
• Review PlayPosit and discussion questions and ask faculty, Gabriel, or Emlen any questions you have.
• (Optional) Prepare a presentation.

During Class

• (5 min) Come up with some fun way to assign the roles of spokesperson and notetaker (e.g. earliest birthday in the year, lives furthest from campus). Remind them of the responsibilities of these roles.
• ([#] min) [Description of some module from #Lesson Content]
• (5 min) Collect questions for plenary.

Lesson Content

Clicker Question

1. Question
   1. Option 1
   2. Options 2

Activity 1: Name

[Brief description of and motivation for the activity]

Discussion Questions

1. Question 1
   1. Subquestion a

1. 1. Subquestion b

Collect Questions for Plenary

(5 min) Collect remaining questions from the students for faculty in plenary (can be questions for clarification, extension, discussion, etc.), and add [ here].