What Does It Mean to Evaluate?
Building Blocks: Evidence vs. Opinion
The first step in learning to evaluate is understanding the difference between an opinion and a judgment. An opinion is what you feel or believe (e.g., "I think summer is the best season"). A judgment, in the context of evaluation, is a conclusion reached after looking at evidence. It is an opinion supported by proof.
Imagine two students are looking at a graph showing that the average global temperature has risen by 1.2°C over the last 100 years.
- Opinion: "I don't like hot weather."
- Evaluation: "Based on this evidence of rising temperatures, we can judge that the planet is heating up, which supports the theory of climate change."
Criteria: The Ruler for Your Judgment
When you evaluate something, you need a set of rules or standards to measure it against. These are called criteria. Think of it like judging a diving competition. You don't just say "that was nice." You score based on specific criteria: the difficulty of the dives, the splash size, and the diver's form.
Here’s a table showing how different subjects use different criteria to evaluate:
| Subject | What is Being Evaluated? | Common Criteria |
|---|---|---|
| Science | An Experiment | Was it a fair test? (controlled variables), are the results repeatable? Is the data accurate? |
| History | A Primary Source | Is the source authentic? Was the author biased? Does it match other sources from that time? |
| Economics | A Government Policy | Is it efficient? (cost vs. benefit), is it equitable? (fair for everyone), is it effective? |
| English Class | An Argumentative Essay | Is the thesis clear? Is the evidence relevant and strong? Does the conclusion follow logically? |
Real-World Case: Evaluating Two Phones
Imagine you are helping a friend choose a new smartphone. You have two models, Phone A and Phone B. To make a good evaluation, you need to gather evidence and use clear criteria.
First, you decide on your criteria. Since your friend loves taking photos and is on a budget, you choose: Camera Quality and Price. Then, you gather evidence from expert reviews and store websites.
| Criterion | Phone A (Evidence) | Phone B (Evidence) |
|---|---|---|
| Camera Quality | 50 MP camera, excellent low-light performance (expert review score: 9/10) | 12 MP camera, good daylight photos but poor in low light (expert review score: 6/10) |
| Price | $799 | $499 |
Your Evaluation: "Based on the evidence, Phone A has a significantly better camera, which meets your primary need. However, it costs $300 more. If camera quality is the most important factor, I judge Phone A to be the better choice despite the higher price. If saving money is more critical, then Phone B is the better option."
Important Questions About Evaluation
❓ Isn't evaluating just the same as criticizing?
No, not at all. To criticize often means to find faults, but to evaluate means to weigh the good and the bad. For example, an evaluation of a movie might praise its special effects (strength) while noting its weak story (weakness), leading to a balanced judgment.
❓ How can my evaluation be wrong if it's my judgment?
A judgment can be wrong if it is based on weak or incorrect evidence. If you judge that a new fertilizer helps plants grow just because one plant looked greener, but you forgot to water the other plant (the control), your judgment is flawed. A strong evaluation is only as good as the evidence and reasoning behind it.
❓ Do I always need numbers and data to evaluate?
Not always. While numbers are powerful evidence, you can also use qualitative evidence. For example, to evaluate which historical novel better captures the spirit of the 1920s, you would use evidence like descriptions of fashion, language, and social attitudes found in the books, compared to historical records.
Footnote
[1] Criteria: The standards or rules used as the basis for a judgment. For example, "safety" and "fuel efficiency" are common criteria for judging a car.
[2] Qualitative Evidence: Evidence based on qualities or characteristics that are difficult to measure with numbers, like descriptions, feelings, or interviews.