Calculate Number Set Basics from

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You entered a number set X of {170,280,1300}

From the 3 numbers you entered, we want to calculate the mean, variance, standard deviation, standard error of the mean, skewness, average deviation (mean absolute deviation), median, mode, range, Pearsons Skewness Coefficient of that number set, entropy, mid-range

Sort Ascending from Lowest to Highest

170, 280, 1300

Rank Ascending

170 is the 1st lowest/smallest number

280 is the 2nd lowest/smallest number

1300 is the 3rd lowest/smallest number

Sort Descending from Highest to Lowest

1300, 280, 170

Rank Descending

1300 is the 1st highest/largest number

280 is the 2nd highest/largest number

170 is the 3rd highest/largest number

Ranked Data Calculation

Sort our number set in ascending order

and assign a ranking to each number:

Ranked Data Table

Step 2: Using original number set, assign the rank value:

Since we have 3 numbers in our original number set,
we assign ranks from lowest to highest (1 to 3)

Our original number set in unsorted order was 170,280,1300

Our respective ranked data set is 1,2,3

Root Mean Square Calculation

where A = x₁² + x₂² + x₃² and N = 3 number set items

Calculate A

A = 170² + 280² + 1300²

A = 28900 + 78400 + 1690000

A = 1797300

Calculate Root Mean Square (RMS):

RMS = 774.01550372069

Central Tendency Calculation

Central tendency contains:
Mean, median, mode, harmonic mean,
geometric mean, mid-range, weighted-average:

Calculate Mean (Average) denoted as μ

μ = 583.33333333333

Calculate the Median (Middle Value)

Since our number set contains 3 elements which is an odd number,
our median number is determined as follows:

Number Set = (n₁,n₂,n₃)

Median Number = Entry ½(n + 1)

Median Number = Entry ½(4)

Median Number = n₂

Therefore, we sort our number set in ascending order

Our median is entry 2 of our number set highlighted in red:

(170,280,1300)

Median = 280

Calculate the Mode - Highest Frequency Number

The highest frequency of occurence in our number set is 1 times
by the following numbers in green:

()

Since the maximum frequency of any number is 1, no mode exists.

Mode = N/A

Calculate Harmonic Mean:

With N = 3 and each x_i a member of the number set you entered, we have:

Harmonic Mean = 293.45558014543

Calculate Geometric Mean:

Geometric Mean = (x₁ * x₂ * x₃)^1/N

Geometric Mean = (170 * 280 * 1300)^1/3

Geometric Mean = 61880000^{0.33333333333333}

Geometric Mean = 395.53364820434

Calculate Mid-Range:

Mid-Range = 735

Stem and Leaf Plot

Take the first digit of each value in our number set

Use this as our stem value

Use the remaining digits for our leaf portion

Sort our number set in descending order:

{1300,280,170}

Calculate Variance denoted as σ²

Let's evaluate the square difference from the mean of each term (X_i - μ)²:

(X₁ - μ)² = (170 - 583.33333333333)² = -413.33333333333² = 170844.44444444

(X₂ - μ)² = (280 - 583.33333333333)² = -303.33333333333² = 92011.111111111

(X₃ - μ)² = (1300 - 583.33333333333)² = 716.66666666667² = 513611.11111111

Adding our 3 sum of squared differences up

ΣE(X_i - μ)² = 170844.44444444 + 92011.111111111 + 513611.11111111

ΣE(X_i - μ)² = 776466.66666667

Use the sum of squared differences to calculate variance

Calculate the Standard Error of the Mean:

Calculate Skewness:

Let's evaluate the square difference from the mean of each term (X_i - μ)³:

(X₁ - μ)³ = (170 - 583.33333333333)³ = -413.33333333333³ = -70615703.703704

(X₂ - μ)³ = (280 - 583.33333333333)³ = -303.33333333333³ = -27910037.037037

(X₃ - μ)³ = (1300 - 583.33333333333)³ = 716.66666666667³ = 368087962.96296

Add our 3 sum of cubed differences up

ΣE(X_i - μ)³ = -70615703.703704 + -27910037.037037 + 368087962.96296

ΣE(X_i - μ)³ = 269562222.22222

Calculate skewnes

Skewness = 1.0235917520017

Calculate Average Deviation (Mean Absolute Deviation) denoted below:

Evaluate the absolute value of the difference from the mean

|X_i - μ|:

|X₁ - μ| = |170 - 583.33333333333| = |-413.33333333333| = 413.33333333333

|X₂ - μ| = |280 - 583.33333333333| = |-303.33333333333| = 303.33333333333

|X₃ - μ| = |1300 - 583.33333333333| = |716.66666666667| = 716.66666666667

Average deviation numerator:

Σ|X_i - μ| = 413.33333333333 + 303.33333333333 + 716.66666666667

Σ|X_i - μ| = 1433.3333333333

Calculate average deviation (mean absolute deviation)

Average Deviation = 477.77778

Calculate the Range

Range = Largest Number in the Number Set - Smallest Number in the Number Set

Range = 1300 - 170

Range = 1130

Calculate Pearsons Skewness Coefficient 1:

Since no mode exists, we do not have a Pearsons Skewness Coefficient 1

Calculate Pearsons Skewness Coefficient 2:

PSC2 = 1.7887

Calculate Entropy:

Entropy = Ln(n)

Entropy = Ln(3)

Entropy = 1.0986122886681

Calculate Mid-Range:

Mid-Range = 735

Calculate the Quartile Items

We need to sort our number set from lowest to highest shown below:

{170,280,1300}

Calculate Upper Quartile (UQ) when y = 75%:

V = 3 ← Rounded down to the nearest integer

Upper quartile (UQ) point = Point # 3 in the dataset which is 1300

Calculate Lower Quartile (LQ) when y = 25%:

V = 1 ← Rounded up to the nearest integer

Lower quartile (LQ) point = Point # 1 in the dataset which is 170

170,280,1300

Calculate Inter-Quartile Range (IQR):

IQR = UQ - LQ

IQR = 1300 - 170

IQR = 1130

Calculate Lower Inner Fence (LIF):

Lower Inner Fence (LIF) = LQ - 1.5 x IQR

Lower Inner Fence (LIF) = 170 - 1.5 x 1130

Lower Inner Fence (LIF) = 170 - 1695

Lower Inner Fence (LIF) = -1525

Calculate Upper Inner Fence (UIF):

Upper Inner Fence (UIF) = UQ + 1.5 x IQR

Upper Inner Fence (UIF) = 1300 + 1.5 x 1130

Upper Inner Fence (UIF) = 1300 + 1695

Upper Inner Fence (UIF) = 2995

Calculate Lower Outer Fence (LOF):

Lower Outer Fence (LOF) = LQ - 3 x IQR

Lower Outer Fence (LOF) = 170 - 3 x 1130

Lower Outer Fence (LOF) = 170 - 3390

Lower Outer Fence (LOF) = -3220

Calculate Upper Outer Fence (UOF):

Upper Outer Fence (UOF) = UQ + 3 x IQR

Upper Outer Fence (UOF) = 1300 + 3 x 1130

Upper Outer Fence (UOF) = 1300 + 3390

Upper Outer Fence (UOF) = 4690

Calculate Suspect Outliers:

Suspect Outliers are values between the inner and outer fences

We wish to mark all values in our dataset (v) in red below such that -3220 < v < -1525 and 2995 < v < 4690

170,280,1300

Calculate Highly Suspect Outliers:

Highly Suspect Outliers are values outside the outer fences

We wish to mark all values in our dataset (v) in red below such that v < -3220 or v > 4690

170,280,1300

Calculate weighted average

170, 280, 1300

Weighted-Average Formula:

Multiply each value by each probability amount

We do this by multiplying each X_i x p_i to get a weighted score Y

Weighted Average = 0

Frequency Distribution Table

Show the freqency distribution table for this number set

170, 280, 1300

Determine the Number of Intervals using Sturges Rule:

We need to choose the smallest integer k such that 2^k ≥ n where n = 3

For k = 1, we have 2¹ = 2

For k = 2, we have 2² = 4 ← Use this since it is greater than our n value of 3

Therefore, we use 2 intervals

Our maximum value in our number set of 1300 - 170 = 1130

Each interval size is the difference of the maximum and minimum value divided by the number of intervals

Add 1 to this giving us 565 + 1 = 566

Frequency Distribution Table

Successive Ratio Calculation

Go through our 3 numbers

Determine the ratio of each number to the next one

Successive Ratio 1: 170,280,1300

170:280 → 0.6071

Successive Ratio 2: 170,280,1300

280:1300 → 0.2154

Successive Ratio Answer

Successive Ratio = 170:280,280:1300 or 0.6071,0.2154

Final Answers