Accuracy and Precision

[baig_anora]

Hi,

I am Baig, Trainee Engineer in Analog Testing.

Can anyone help me in understanding the difference between the terms 'Accuracy' and 'Precision'. I knew it is very important to understand the difference for a test engineer.

Thanks.

 

[papunblg]

Hi,

I am Baig, Trainee Engineer in Analog Testing.

Can anyone help me in understanding the difference between the terms 'Accuracy' and 'Precision'. I knew it is very important to understand the difference for a test engineer.

Thanks.

In the fields of science, engineering, industry and statistics, the accuracy of a measurement system is the degree of closeness of measurements of a quantity to that quantity's actual (true) value. The precision of a measurement system, also called reproducibility or repeatability, is the degree to which repeated measurements under unchanged conditions show the same results.
See https://en.wikipedia.org/wiki/Accuracy_and_precision

---------- Post added at 12:08 ---------- Previous post was at 12:06 ----------

**broken link removed**

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See Error, Accuracy, and Precision **broken link removed**

see https://www.google.com/search?sourc...DFA_enIN419IN419&q='Accuracy'+and+'Precision'

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It is important to distinguish from the start a different between accuracy and precision:

1) Accuracy is the degree to which information on a map or in a digital database matches true or accepted values. Accuracy is an issue pertaining to the quality of data and the number of errors contained in a dataset or map. In discussing a GIS database, it is possible to consider horizontal and vertical accuracy with respect to geographic position, as well as attribute, conceptual, and logical accuracy.
The level of accuracy required for particular applications varies greatly.
Highly accurate data can be very difficult and costly to produce and compile.

2) Precision refers to the level of measurement and exactness of description in a GIS database. Precise locational data may measure position to a fraction of a unit. Precise attribute information may specify the characteristics of features in great detail. It is important to realize, however, that precise data--no matter how carefully measured--may be inaccurate. Surveyors may make mistakes or data may be entered into the database incorrectly.
The level of precision required for particular applications varies greatly. Engineering projects such as road and utility construction require very precise information measured to the millimeter or tenth of an inch. Demographic analyses of marketing or electoral trends can often make do with less, say to the closest zip code or precinct boundary.
Highly precise data can be very difficult and costly to collect. Carefully surveyed locations needed by utility companies to record the locations of pumps, wires, pipes and transformers cost $5-20 per point to collect.
High precision does not indicate high accuracy nor does high accuracy imply high precision. But high accuracy and high precision are both expensive.

 

[baig_anora]

Hi, Rajashekar

The reply u sent has helped me. I could understand something form the images you attached. But i can find this information in inernet also. It would have been very useful for me if you explained in your own words.

Thanks.

---------- Post added at 12:53 ---------- Previous post was at 12:52 ----------

Hi, Rajashekar

The reply u sent has helped me. I could understand something form the images you attached. But i can find this information in inernet also. It would have been very useful for me if you explained in your own words.

Thanks.

 

[ashugtiwari]

Hi, Rajashekar

The reply u sent has helped me. I could understand something form the images you attached. But i can find this information in inernet also. It would have been very useful for me if you explained in your own words.

Thanks.

---------- Post added at 12:53 ---------- Previous post was at 12:52 ----------

Hi, Rajashekar

The reply u sent has helped me. I could understand something form the images you attached. But i can find this information in inernet also. It would have been very useful for me if you explained in your own words.

Thanks.

In simple words, what Rajsekhar said is;
In football/foosball, when u kick a ball for goal, if the ball goes in exact center of goalpost or not that accuracy.
And how often(repeatedly) do u actually able to make goals at the center of goalpost all the time u kick the ball, thats pricision.

for eg. if u shoot 5 times towards goalpost and all goes to goalpost except one misses the center of goalpost, instead goes to other area. So u r 100% accurate when it hits center and 0% when u don't but u are 80% precise in making center goals considering all 4/5 goals.

 

[papunblg]

In simple words, what Rajsekhar said is;
In football/foosball, when u kick a ball for goal, if the ball goes in exact center of goalpost or not that accuracy.
And how often(repeatedly) do u actually able to make goals at the center of goalpost all the time u kick the ball, thats pricision.

for eg. if u shoot 5 times towards goalpost and all goes to goalpost except one misses the center of goalpost, instead goes to other area. So u r 100% accurate when it hits center and 0% when u don't but u are 80% precise in making center goals considering all 4/5 goals.

Good explanation