Video summary

The Language of Research: Validity, Reliability, Credibility and Bias

Main summary

Key takeaways

Educational

Main ideas / lessons from the video

1) Bias

Bias occurs when only one side of a discussion/issue is presented, or when data/sources are skewed toward a particular viewpoint.

Where bias can appear

  • Primary or secondary resources
  • Media articles
  • Biased data from surveys or research

Example approach (politicians)

  • A politician may publicly support a person/issue and write or promote an article that aligns with that support.
  • Check whether the politician has something to gain (e.g., financial or political interests).

Types of bias

  • Intentional bias
    • The author has a stake and purposefully presents only one side.
    • They may omit contrary viewpoints.
    • Can include exaggeration of benefits (e.g., overstating profits/jobs from the oil industry).
  • Omission
    • A “tricky” form of bias where important information/views are not included.
    • You look for what is missing (e.g., an article supporting oil does not mention environmental impacts or other relevant counterpoints).
  • Biased sample (common in surveys/interviews)
    • The group surveyed/interviewed is not representative.
    • Example: if a survey about “what Australia thinks about the oil issue” only polls oil workers/industry employees, responses will likely favor the industry because of their incentives.

How to detect bias (step-by-step checklist)

  • Identify who is writing/producing the source.
  • Ask:
    • Do they have something to gain or something to lose?
    • What have they invested in (money, career interests)?
    • Who stands to gain (a company, political party, etc.)?
    • Do they have supporting evidence (facts/statistics)?
    • Is more than one side of the issue presented?

2) Reliability

Reliability means consistency of results—would you get the same outcomes again under similar conditions?

Core idea

  • If results vary widely with repetition, the measure is not reliable.
  • Example: a carnival guesser changes their estimated weight each time (not reliable), while bathroom scales give consistent readings (reliable).

How to ensure reliability (instructions)

  • For primary sources (surveys, interviews)
    • If you repeat the survey/interview with a similar sample at a different time, do you get similar results?
    • Repeating the process multiple times increases the likelihood the data is reliable.
  • For secondary sources
    • Check whether the findings/data are consistent with other articles or datasets.
    • Confirm whether sources generally agree (similar conclusions).

Also considered

  • How credible the source is (mentioned as tied into checking quality).

3) Validity

Validity means accuracy and correct measurement—is the source really measuring what it claims to measure, and is it relevant to your topic?

Difference from reliability

  • Reliability = consistency
  • Validity = correct/accurate measurement of the intended concept

Example

  • Even if something is “supposed” to measure weight, broken scales produce wrong results—so the measurement is not valid.

How to ensure validity (instructions)

  • For primary resources (surveys/interviews)
    • Ask the right questions that match what you want to measure.
    • Avoid vague/ambiguous questions (example: asking about “Brighton” could mean a suburb or a school).
    • Keep variables controlled:
      • Don’t ask the same question under different conditions that could change opinions (e.g., start of year vs. sports day vs. exam week), if you want a consistent comparison.
  • For secondary sources
    • Ensure the source relates directly to your topic (not merely “somewhat related”).
    • Be careful with generalizations:
      • Don’t take a claim about “Brighton Secondary School is exemplary” and automatically generalize it to “Brighton suburb is exemplary.”
    • Again, consider credibility of the author/researcher and whether they are an expert.

4) Credibility

Credibility means the source can be trusted—it can be believed.

How credibility works

  • Credible sources provide a unique perspective, often from experts
  • Claims are corroborated by other people/sources
  • Check whether the source is contradicted by most others:
    • If one source disagrees with everything else, reassess whether it’s credible

What to check about the author

  • Are they qualified?
  • Who are they employed by?
  • What is their experience in that topic?

Summary section (as stated in the video)

  • Bias: only one side presented
  • Reliability: consistency of measures/results
  • Validity: accuracy and measuring what it’s supposed to measure (relevant to the topic)
  • Credibility: trustworthy sources (can be believed)

Speakers / sources featured

  • Speaker: An unnamed presenter (referred to as “hi guys” / “see you in class guys bye”; no specific name given)
  • Sources/examples referenced (not real named sources):
    • Politicians
    • Media articles
    • Oil industry / “Mr oil” example
    • Physiotherapists (as an example of a potentially interest-linked author)
    • “Joe Blow from down the road” (generic placeholder example)
    • Bathroom scales / weight-guessing carnival (illustrative example)

Original video