ERRORS AND STATISTICS

Question 1

Entails the entire process of obtaining a desired quantity, including preparations (instrument calibration and setup), pointing, matching, and comparing

Answer 1

Measurement

Question 2

Process of determining the extent, size or dimensions of a particular quantity in comparison to a given standard

Answer 2

Measurement

Question 3

Consists of several physical operations which renders numerical value

Answer 3

Measurement

Question 4

Measurements are numerical values for random variables which are subject to

Answer 4

statistical fluctuations

Question 5

due to observational errors

Answer 5

Statistical variations

Question 6

refers to the difference between the measured or calculated value of a quantity and a given or established (true) value of that quantity

Answer 6

ERROR

Question 7

Formula for error

Answer 7

refers to the difference between the measured or
calculated value of a quantity and a given or established
(true) value of that quantity

Question 8

Formula for error

Answer 8

𝜺 = 𝒙 − 𝝉

Question 9

negative of error

Answer 9

Correction

Question 10

Formula of Correction

Answer 10

𝐂𝐨𝐫𝐫𝐞𝐜𝐭𝐢𝐨𝐧 = − (𝒙 − 𝝉)

Question 11

SOURCES OF ERRORS

Answer 11

Natural Errors
Instrumental Errors
Personal Errors

Question 12

Occurs due to variations of natural phenomena such as changes in temperature, humidity, wind velocity, magnetic declination, refraction, etc.

Answer 12

Natural Errors

Question 13

Arises due to imperfections or faulty adjustment of instruments.

Answer 13

Instrumental Errors

Question 14

Arises principally due to limitations of the senses of sights, touch and hearing of the observer.

Answer 14

Personal Errors

Question 15

Types of Errors

Answer 15

Mistake or blunders
Systematic Errors
Random/Accidental Errors

Question 16

Occurs due to lack of experience, carelessness, poor judgement, confusion in the observations

If the mistake remain undetected, it may produce
serious effect on the whole work

Answer 16

Mistake or blunders

Question 17

Common Mistakes/blunders

Answer 17

➢ Reading the wrong graduation on the tape
➢ Omitting a whole length of tape
➢ Reading a scale backward
➢ Sighting the wrong target
➢ Incorrect recording of field notes
➢ Transposition of figures
➢ Misplacing a decimal point

Question 18

is a cumulative error that occur under the same conditions.

Answer 18

Systematic Errors

Question 19

Caused by physical and natural conditions that vary in accordance with known mathematical or physical laws.

Answer 19

Systematic Errors

Question 20

Common Systematic Errors

Answer 20

➢ Equipment out of calibration
➢ Personal biases of the observer
➢ Use of incorrect units (feet instead of meters)

Question 21

Produced by irregular causes that are beyond the control of the observer

Answer 21

Random/Accidental Errors

Question 22

This variation results from observational errors which have known functional relationship based upon deterministic system

Answer 22

Random/Accidental Errors

Question 23

Refers to the degree of agreement/consistency between several measurements of a quantity.

Answer 23

Precision

Question 24

It is a measure of uniformity of the outcome/result

Answer 24

Precision

Question 25

Refers to the degree of conformity/closeness of a measured value with the absolute/true value of the quantity.

Answer 25

Accuracy

Question 26

General Uses of Statistics

Answer 26

Statistics aids in decision making ❑ Provides comparison ❑ Explains action that has taken place ❑ Justifies a claim or assertion ❑ Predicts future outcome ❑ Estimates unknown quantities Statistics summarizes data for public use

Question 27

MEASURES OF CENTRAL TENDENCY

Answer 27

➢ Mean ➢ Median ➢ Midrange ➢ Mode

Question 28

Sum of all the values of the observations divided by the number of observations

Answer 28

Sample Mean

Question 29

Most Probable Value (MPV)

Answer 29

Sample Mean

Question 30

Most familiar measure of central tendency used

Answer 30

Sample Mean

Question 31

positional middle of the arrayed data

Answer 31

Sample Median

Question 32

Value of observation that is midway along the range

Answer 32

Midrange

Question 33

Value that occurs most frequently in the sample

Answer 33

Sample Mode

Question 34

The total spread of the sample

Answer 34

Range

Question 35

Parameter of dispersion or spread

Answer 35

Variance

Question 36

Defined as the positive square root of the variance

Answer 36

Standard Deviation

Question 37

Refers to the ratio of the error to the measured or estimated quantity

Answer 37

Relative Error/Precision

Question 38

Refers to the ratio between the total error and the total length of the survey.

Answer 38

Ratio of Misclosure