Theoretical Definition – Range

Statistical Range can be defined as any two values that can imply that intermediate numbers can exist between these two values.

**Example**

The Age Range of 21-30 can suggest that these integrer (whole number) age values exist 21, 22, 23, 24, 25, 26, 27, 28, 29, and 30 between these Range limits. Generally, it can suggest that all intermediate values between 21 and 30 can be described by these two numbers, Integers and non-integer values.

Upper and Lower Range limits

However, a problem can arise.

**Example**

Let’s suppose that you have conducted a survey and in that survey, you made two Age groups: 21-30 and 31 to 40. However, a participant told you that his age was 30 years and 6 months, that is, he was 30.5 years old. What will you decide? You will include him in the first or in the latter Age Range / Group? This problem exists in all Lower and Upper Range Limits.

Convienient Lower and Upper Range Limits

The convenient Lower and Upper limits are the two Declared values.

For Example, The Convenient Lower and Upper Range Limits for the age groups of 21-30, and 31-40 are the values of 21 and 30, and the values of 31 and 40, respectively.

True Lower and Upper Range Limits

The Real True Lower and Upper Limits can be calculated if:

i) We substcact “5” points from the most previous “Decimal Depth” of the Convenient Lower Range Limit Value.

ii) We add “5” points to the most previous “Decimal Depth” of the Convenient Upper Range Limit Value.

True Lower and Upper Range Limits: Examples

The Whole numbers / Integer values have zero “0” “Decimal depth”. We add “1” point in order to find the most previous “Decimal depth” for an Integer value.

**True Lower Range Limits**

A “Convenient” Lower Range Limit value of “1” has a “True” Lower Range Limit value of:

and a “Convenient” Lower Range Limit value of “0.04” has a “True” Lower Range Limit value of:

Here, the Decimal Depth of the “Convenient” Lower Range Limit value is 2. The most previous Decimal Depth is found by adding a point to this value: . From this “Decimal depth”, the value of “5” is substracted from the “Convenient” Lower Range Limit value.

**True Upper Range Limit**

A “Convenient” Upper Range Limit value of “10” has a “True” Upper Range Limit value of:

and a “Convenient” Upper Range Limit value of “0.001” has a “True” Upper Range Limit value of:

Here, the Decimal Depth of the “Convenient” Upper Range Limit value is 3. The most previous Decimal Depth is found by adding a point to this value: . From this “Decimal depth”, the value of “5” is added to the “Convenient” Upper Range Limit value.

**Table that presents the “Convenient” and True Upper and Lower Range Limtis in various examples**

Convenient Range Limits | True Range Limits |
---|---|

21 --- 30 | 20.5 --- 30.5 |

1 --- 10 | 0.5 --- 10.5 |

0.04 --- 0.001 | 0.035 --- 0.0015 |

-0.33 --- +0.33 | -0.325 --- +0.335 |

0 --- 1 | -0.5 --- 1.5 |

-1--- 0 | -1.5 --- 0.5 |

The Size of the Range – Whole numbers / integer case

Statistically, the size of the Range for integer numbers (Range Represantation) can be found by this way: *“Upper Range Limit” – “Lower Range Limit” + 1*.

Therefore, according to the previous example:

This result shows that there are ten integer values that can be represented by the Range of 21-30.

Size of the Range – General Formula

In the previous example, we suggested that there were zero “0” decimals, in order to find the quantity of the integer values that can be represented by a Range with Integer Upper and Lower Limits. The Statistical Formula for such calculation is the below one, which is the simplified edition of the next one, because :

Now, if we would like to increase the “depth”, that is, to increase the decimal “depth” in a given Range, then the General Range Formula can be defined as:

i) We subtract the “Upper” Range Limit from the “Lower” Range Limit

ii) For Decimal depth of zero “0”, we multiply the result by “1”: (default value)

iii) For Decimal depth greater than zero (>0) , we add so many zeros to the default value of “1”, as the number of decimals we are interested in to find Range Value Representation, and then:

iv) We add to this final result “one point” in order to find the Range Value Representation or Range Width .

Applying the Formula

1) For the Range of 1.0 to 3.0, the Decimal Depth is “1”, and thus:

and then:

Therefore, the Range of 1.0 to 3.0 represents 21 values in a Decimal Depth of “0.1”.

2) For the Range of -0.2 to 0.5, the Decimal Depth is “1”, and thus:

and then:

Therefore, the Range of -0.2 to 0.5 represents 71 values in a decimal Decimal Depth of “0.1”.

3) For the Range of 0.001 to 0.002, the Decimal Depth is “3”, and thus:

and then:

Therefore, the Range of 0.001 to 0.002 represents 2 values in a Decimal Depth of “0.001”: 0.001 and 0.002!

4) For the Range of 0.10 to 0.02, the Decimal Depth is “2”, and thus:

and then:

Therefore, the Range of 0.10 to 0.02 represents 9 values in a Decimal Depth of “0.01”:

!

5) For the Range of 2 to 1.001 –> the Decimal Depth is “3”, and thus:

and then:

Therefore, the Range of 2 to 1.001 represents 1000 values.

**Table that presents the “Range Value Representation” in relation to the Decimal Depth of the Range “0 to 1″**

Decimal Depth | Range Value Representation FOR the range of 0-1 |
---|---|

0 | 2 |

1 | 11 |

2 | 101 |

3 | 1001 |

4 | 10001 |

5 | 10001 |

6 | 100001 |

7 | 1000001 |

8 | 10000001 |

9 | 100000001 |

10 | 1000000001 |