Versus

“Accuracy” vs. “Precision”

Nouns, Versus

I frequently hear people confuse accuracy and precision.

Problem:
These two nouns are not synonyms, at least not in science.

Explanation:
The scientific definition of the noun “accuracy” is the degree to which a measurement agrees with that measurement’s standard value.

The scientific definition of the noun “precision” is the degree to which a set of measurements of the same sample agree with that set’s mean.

Imagine an archery target, and imagine an archer shooting arrows at that target.

The closer that an arrow lands to the center of the target (the bull’s eye), the more accurate is the shot.

In contrast, if an archer can shoot several arrows that all land in almost the same location, then one can say that the archer is precise.

An archer can be accurate simply by the fact that bull’s eye is the mean of the points at which all of his or her arrows land.

An archer can be precise simply by the fact that all of his or her arrows land in the same location.

Precision speaks to reproducibility and standard deviation within the sample. Higher precision in a trial (e.g., in shooting a set of arrows) refers to greater reproducibility and smaller standard deviation.

Accuracy speaks to nearness to the target. Higher accuracy in a trial (e.g., in shooting a set of arrows) refers to less distance between the target location or value and the mean of the actual locations or values.

This discussion has these implications:

  • A trial can be accurate but not precise.
  • A trial can be precise but not accurate.
  • An ideal trial is both accurate and precise.
  • One can make a calculated adjustment for a trial that is precise but not accurate (that is, a trial that is biased), if one knows the degree of inaccuracy (the degree of bias).
  • One can ignore a trial’s imprecision (the degree of variability) in a trial that is accurate but not precise, if one’s primary interest is that the mean within the trial is very close to the goal or target.

Solution:
Think “nearness to a goal” when thinking of accuracy. Think “reproducibility” when thinking of precision.

“Bake” vs. “Roast”

Verbs, Versus

I thought about these two verbs the other day and wondered what the distinction was.

Problem:
Some people use these verbs interchangeably, but they are not quite synonyms.

Explanation:
Some say that roasting specifically applies to meat.

Others say that one can roast vegetables, too.

For example, some say that a roasted potato differs from a baked potato in that the roasted potato is cooked in an oven with liquids poured over it while the baked potato is cooked in an oven without such liquids.

I wondered whether this was the best distinction, so I read the definition of each verb in a dictionary.

The verb “roast” — when it comes to food — specifically means to bake uncovered, and the verb “roast” applies to both meat and other food.

In other words, to roast a potato is to bake it uncovered, usually in an oven.

Whether the potato is cooked with liquids is immaterial to whether it is roasted.

Solution:
Think of roasting as a special way of baking — that is, baking food uncovered.

“I feel bad.” vs. “I feel badly.”

Adjectives, Adverbs, Verbs, Versus

I thought again about these two forms after hearing someone claim that only one of these was correct.

Problem:
The verb “feel” can take an adjective or an adverb.

Explanation:
The verb “feel” is a loaded verb in that it relates to a state of health or emotion as well as to the sense of touch.

The verb “feel” can be used as a linking verb, which is called a “copula” in linguistics.

A linking verb ties the subject of a sentence with the predicate of the sentence.

As described elsewhere, the verbs “be”, “become”, and “seem” are called true linking verbs because they can be nothing else.

Examples include:

  • “I am rich!”
  • “You became wealthy.”
  • “They seem nice.”

In contrast, each of the following verbs can act as an action verb or as a linking verb:

  • “appear”;
  • “feel”;
  • “grow”
  • “look”;
  • “prove”;
  • “remain”;
  • “smell”;
  • “sound”;
  • “taste”;
  • “turn”.

Here are examples of these verbs used as action verbs, each of which can be modified by one or more adverbs:

  • “She effortlessly appeared from the bushes.”
  • “He barely feels that tack in the carpet.”
  • “Mary often grows hibiscus plants.”
  • “Look now at that cow crossing the road!”
  • “Can you quickly prove this theorem?”
  • “I can remain here.”
  • “Everyone should always smell the flowers.”
  • “Paul Revere urgently sounded the alarm.”
  • “Can they barely taste the ginger in that dessert?”
  • “Please slowly turn the car to the right at the next light.”

Here are examples of the same verbs used as linking verbs, each of which is followed by an adjective:

  • “She appears ill.”
  • “He feels odd.”
  • “Mary grows angry when she sees her hibiscus flowers destroyed.”
  • “Darling, you look marvelous!”
  • “Purchase of Manhattan proved inexpensive.”
  • “The dishes remain dirty.”
  • “You smell delightful.”
  • “His argument sounds correct.”
  • “This dessert tastes delicious.”
  • “His face turns red when you embarrass him.”

Solution:
Use “I feel bad.” to describe the current state of your emotions or health. Use “I feel badly.” to describe your ability to feel with your sensory neurons.