I hear all the time estimating is the same as guessing. This is not true mathematically nor is not true business process wise. This is an approach used by many (guessing), not understanding that making decisions in the presence of uncertainty requires we understand the impact of that decision. When that future is uncertain, we need to know that impact in probabilistic terms. And with this, comes confidence, precision, and accuracy of the estimate.
What’s the difference between estimate and guess? The distinction between the two words is one of the degree of care taken in arriving at a conclusion.
The word Estimate is derived from the Latin word aestimare, meaning to value. The term is has the origin of estimable, which means capable of being estimated or worthy of esteem, and of course esteem, which means regard as in High Regard.
To estimate means to judge the extent, nature, or value of something - connected to the regard - he is held in high regard, with the implication that the result is based on expertise or familiarity. An estimate is the resulting calculation or judgment. A related term is approximation, meaning close or near.
In between a guess and an estimate is an educated guess, a more casual estimate. An idiomatic term for this type of middle-ground conclusion is ballpark figure. The origin of this American English idiom, which alludes to a baseball stadium, is not certain, but one conclusion is that it is related to in the ballpark, meaning close in the sense that one at such a location may not be in a precise location but is in the stadium.
To guess is to believe or suppose, to form an opinion based on little or no evidence, or to be correct by chance or conjecture. A guess is a thought or idea arrived at by one of these methods. Synonyms for guess include conjecture and surmise, which like guess can be employed both as verbs and as nouns.
We could have a hunch or an intuition, or we can engage in guesswork or speculation. Dead reckoning is same thing as guesswork. Dead reckoning was originally referred to a navigation process based on reliable information. Near synonyms describing thoughts or ideas developed with more rigor include hypothesis and supposition, as well as theory and thesis.
A guess is a casual, perhaps spontaneous conclusion. An estimate is based on intentional thought processes supported by data.
What Does This Mean For Projects?
If we're guessing we're making uninformed conclusions usually in the absence of data, experience, or any evidence of credibility. If we're estimating we are making informed conclusions based on data, past performance, models - including Monte Carlo models, and parametric models.
When we hear decisions can be made without estimates. Or all estimating is guessing, we now mathematically and business process - neither of this is true.
This post is derived from Daily Writing Tips