Table with Class Intervals (with Frequencies)

County Aggravated Assault Cases (𝑥) Frequency (𝑓) 𝑓 * 𝑥
Allen 10 1 10
Belmont 27 1 27
Carroll 2 1 2
Clermont 85 1 85
Fairfield 33 1 33
Fulton 7 1 7
Geauga 3 1 3
Greene 20 1 20
Hamilton 81 1 81
Hocking 16 1 16
Jefferson 9 1 9
Lawrence 39 1 39
Licking 34 1 34
Lorain 35 1 35
Lucas 67 1 67
Madison 6 1 6
Mahoning 0 1 0
Medina 7 1 7
Miami 26 1 26
Montgomery 157 1 157
Perry 4 1 4
Pickaway 17 1 17
Portage 304 1 304
Richland 20 1 20
Stark 59 1 59
Summit 44 1 44
Union 16 1 16
Wood 7 1 7
𝚺𝑓 = 28 𝚺𝑓𝑥 = 1135

Measures of Center

Mean (𝑥̄)

𝑥̄ = 𝚺𝑓𝑥 ÷ 𝚺𝑓
𝑥̄ = 1135 ÷ 28
𝑥̄ = 40.535714285714285

The average aggravated assault cases per county for all 28 counties is approximately 41 cases.

Median (𝑥̃)

𝚺𝑓 = 28

With the sample size being an even number, this means that the median will be between the 14th and 15th data values after sorting the data in ascending order.

Sorted data in ascending order:  0, 2, 3, 4, 6, 7, 7, 7, 9, 10, 16, 16, 17, 20, 20, 26, 27, 33, 34, 35, 39, 44, 59, 67, 81, 85, 157, 304

14th value (2019) = 20
15th value (2019) = 20

𝑥̃ = (𝑥14 + 𝑥15) ÷ 2
𝑥̃ = (20 + 20) ÷ 2
𝑥̃ = 40 ÷ 2
𝑥̃ = 20

The median number of aggravated assault cases in all 28 counties, after the data has been sorted in ascending order, is 20 cases of aggravated assault.

Mode (𝑥̂)

The mode is the data value that has the highest frequency/occurs the most often.

The number of cases of aggravated assault reported the most in 2019 was 7 cases of aggravated assault.

𝑥̂ = 7

Midrange (𝑥MR)

𝑥min = 0 cases
𝑥max = 304 cases

𝑥MR = (𝑥min + 𝑥max) ÷ 2
𝑥MR = (0 + 304) ÷ 2
𝑥MR = 152

Mahoning county had the lowest reported number of aggravated assault cases in 2019: 0 cases of aggravated assault.
Portage county had the highest reported number of aggravated assault cases in 2019: 304 cases of aggravated assault.
The midrange, or average of the minimum and maximum cases of aggravated assaults, is 152 cases of aggravated assault.

Aggravated Assault Cases in Ohio, 2019, sorted in Ascending Order

2019 Aggravated Assault Cases (𝑥) Frequency (𝑓) 𝑥 - 𝑥̄ (𝑥 - 𝑥̄)2 𝑓(𝑥 - 𝑥̄)2
0 1 -40.535714285714285 1643.1441326530612 1643.1441326530612
2 1 -38.535714285714285 1485.001275510204 1485.001275510204
3 1 -37.535714285714285 1408.9298469387754 1408.9298469387754
4 1 -36.535714285714285 1334.8584183673468 1334.8584183673468
6 1 -34.535714285714285 1192.7155612244896 1192.7155612244896
7 3 -33.535714285714285 1124.6441326530612 3373.9323979591836
9 1 -31.535714285714285 994.501275510204 994.501275510204
10 1 -30.535714285714285 932.4298469387754 932.4298469387754
16 2 -24.535714285714285 602.001275510204 1204.002551020408
17 1 -23.535714285714285 553.9298469387754 553.9298469387754
20 2 -20.535714285714285 421.71556122448976 843.4311224489795
26 1 -14.535714285714285 211.28698979591834 211.28698979591834
27 1 -13.535714285714285 183.21556122448976 183.21556122448976
33 1 -7.535714285714285 56.78698979591835 56.78698979591835
34 1 -6.535714285714285 42.71556122448978 42.71556122448978
35 1 -5.535714285714285 30.644132653061213 30.644132653061213
39 1 -1.5357142857142847 2.3584183673469354 2.3584183673469354
44 1 3.4642857142857153 12.001275510204088 12.001275510204088
59 1 18.464285714285715 340.92984693877554 340.92984693877554
67 1 26.464285714285715 700.358418367347 700.358418367347
81 1 40.464285714285715 1637.358418367347 1637.358418367347
85 1 44.464285714285715 1977.0727040816328 1977.0727040816328
157 1 116.46428571428572 13563.929846938778 13563.929846938778
304 1 263.4642857142857 69413.42984693879 69413.42984693879
𝚺𝑓 = 28 𝚺𝑓(𝑥 - 𝑥̄)2 = 103138.9642857143

Measures of Spread

Range

The range of a dataset is equal to the minimum value of the dataset subtracted from the maximum value of the dataset.

𝑥min = 0 cases
𝑥max = 304 cases

range = 𝑥max - 𝑥min
range = 304 - 0
range = 304

Mahoning county had the least amount of reported aggravated assault cases in 2019: 0 cases of aggravated assault.
Portage county had the highest amount of reported aggravated assault cases in 2019: 304 cases of aggravated assault.
The range of number of reported aggravated assault cases between Mahoning and Portage counties in 2019 is 304 cases of aggravated assault.

Variance (𝑠2)

Variance is a measurement that calculates the distance data values have from the mean; it is equal to the square of standard deviation.

𝚺𝑓𝑥 = 1135
𝚺𝑓 = 1135
𝑥̄ = 40.535714285714285 cases

𝑠2 = (𝚺𝑓(𝑥 - 𝑥̄)2) ÷ (𝚺𝑓 - 1)
𝑠2 = (103138.9642857143) ÷ (28 - 1)
𝑠2 = (103138.9642857143) ÷ (27)
𝑠2 = 3819.9616402116408

The variance of the dataset is approximately 3820. This means that there is medium to large spread between the data values and the mean.

Standard Deviation (𝑠)

Standard deviation is the measure of the distance the data values are from the mean. A larger number usually means more spread and variation between the values in the dataset.

𝑠 = √(𝑠2)
𝑠 = √(3819.9616402116408)
𝑠 = 61.80583823727044

The standard deviation is approximately 62. This means that there is medium to large spread between the values of the dataset from the mean.


Measures of Position

The measures of location are found after sorting the data in ascending order. There are 28 numbers in the dataset, which means there are 7 numbers in each quartile (divide the dataset into four parts).

First Quartile: 0 (Mahoning), 2 (Carroll), 3 (Geauga), 4 (Perry), 6 (Madison), 7 (Fulton), 7 (Medina)
Second Quartile: 7 (Wood), 9 (Jefferson), 10 (Allen), 16 (Hocking), 16 (Union), 17 (Pickaway), 20 (Greene)
Third Quartile: 20 (Richland), 26 (Miami), 27 (Belmont), 33 (Fairfield), 34 (Licking), 35 (Lorain), 39 (Lawrence)
Fourth Quartile: 44 (Summit), 59 (Stark), 67 (Lucas), 81 (Hamilton), 85 (Clermont), 157 (Montgomery), 304 (Portage)

The Lower Quartile (25th Percentile) is between 7 (Medina) and 7 (Wood)
Lower Quartile = (𝑥7 + 𝑥8) ÷ 2
Lower Quartile = (7 + 7) ÷ 2
Lower Quartile = 14 ÷ 2
Lower Quartile = 7

When the data for aggravated assault cases in metropolitan counties in Ohio, 2019, is sorted in ascending order, 7 cases of aggravated assault are in the lower quartile, 25 percent.

The Middle Quartile has already been calculated: it is the same as the median (𝑥̃ = 20).
Middle Quartile = 𝑥̃
Middle Quartile = 20

When the data for aggravated assault cases in metropolitan counties in Ohio, 2019, is sorted in ascending order, 20 cases of aggravated assault are in the middle quartile, 50 percent.

The Upper Quartile (75th Percentile) is between 39 (Lawrence) and 44 (Summit)
Upper Quartile = (𝑥21 + 𝑥22) ÷ 2
Upper Quartile = (39 + 44) ÷ 2
Upper Quartile = 83 ÷ 2
Upper Quartile = 41.5

When the data for aggravated assault cases in metropolitan counties in Ohio, 2019, is sorted in ascending order, approximately 41.5 cases are in the upper quartile, 75 percent.

Five-Number Summary

Minimum = 0 (Mahoning)
Q1 = 7
Q2 (median) = 20
Q3 = 41.5
Maximum = 304 (Portage)

Form to calculate Measures of Center

Type your x-values. Separate each with a comma. Do not put a period at the end:


Mean (𝑥̄) =
Median (𝑥̃) =
Mode (𝑥̂) =
Midrange (𝑥MR) =

Form to calculate Measures of Spread

Type your x-values. Separate each with a comma. Do not put a period at the end:


Range =
Variation (𝑠2) =
Standard Deviation (𝑠) =

Form to calculate Measures of Position

Type your x-values. Separate each with a comma. Do not put a period at the end:


Minimum =
Q1 =
Q2(median) =
Q3 =
Maximum =