Scientific observations (a type of evidence) should be objective – they don’t depend on the observer’s point of view. In other words, practically any reasonable observer should be able to agree with the observation.
Qualitative Observations: descriptions that don’t use numbers. They instead describe the qualities of something, such as color, smell, and taste. A description of behavior is also qualitative. Good qualitative observations can be used to do some great scientific studies. In order to be good qualitative observations, they must be objective.
Examples:
•The chimpanzee threw up its arms several times.
•The dog ate a turkey sandwich.
•The taco tasted like garlic.
•The solution gave off a sour odor.
•The box was hot to the touch.
•Small particles were visible on the bottom of the beaker.
•The girl wore a green shirt and blue jeans.
Quantitative Observations: descriptions that use numbers. Sometimes quantitative observations can be better than qualitative observations; for example, if you want to demonstrate that each small increase in room temperature increases students’ aggressive behavior, your case will be more convincing if you actually measure the temperatures and count the aggressive behaviors.
Examples:
•The height of the ceiling is 12 feet.
•The cat weighs 4.5 kg.
•The cat video is 5 minutes and 35 seconds long.
•The dog barked seven times.
•The blood test showed no steroids in the blood sample. (“no” equals zero in this case)
Not Observations
Opinions: statements that depend on the subjective viewpoint of the observer. In other words, these are statements that somebody else might reasonably disagree with. Because they are subjective, they are not usually useful in a scientific study.
Examples:
•The dog was ugly.
•The chimpanzee should settle down.
•The weather was uncomfortably cool.
•The taco needed more paprika to balance out the garlic flavor.
When you record data and observations in a lab, think about what types (qualitative vs. quantitative) you are using. Try to make your observations as objective as possible.