6811944 histogram vg
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Basic Tools for Process Improvement
Module 11
HISTOGRAM
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What is a Histogram?
A Histogram is a vertical bar chart that depicts the distribution of a set of da
Run Charts or Control Charts, which are discussed in other modules, a Hisdoes not reflect process performance over time. It's helpful to think of a Hisas being like a snapshot, while a Run Chart or Control Chart is more like a
(Viewgraph 1).
When should we use a Histogram?When you are unsure what to do with a large set of measurements presenttable, you can use a Histogram to organize and display the data in a more
friendly format. A Histogram will make it easy to see where the majority of falls in a measurement scale, and how much variation there is. It is helpful construct a Histogram when you want to do the following (Viewgraph 2):
! Summarize large data sets graph ically. When you look at Viewgyou can see that a set of data presented in a table isnt easy to use. make it much easier to understand by summarizing it on a tally shee
(Viewgraph 7) and organizing it into a Histogram (Viewgraph 12).
! Compare process results with specification limits. If you add
process specification limits to your Histogram, you can determine quwhether the current process was able to produce "good" products.
Specification limits may take the form of length, weight, density, quanmaterials to be delivered, or whatever is important for the product of
process. Viewgraph 14 shows a Histogram on which the specificatioor "goalposts," have been superimposed. Well look more closely atimplications of specification limits when we discuss Histogram interp
later in this module.
! Communicate information g raphically. The team members cansee the values which occur most frequently. When you use a Histogsummarize large data sets, or to compare measurements to specific
limits, you are employing a powerful tool for communicating informat
! Use a tool to assist in decision making. As you will see as we m
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HISTOGRAM VIEWG
What Is a Histogram?
A bar graph that shows the distribution of data
A snapshot of data taken from a process
0 5 10 15 20 25 30 35 40 45 50 55 60
0
20
40
60
80
100
When Are Histograms Used?
Summarize large data sets graphically
Compare measurements to specification
Communicate information to the team
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What are the parts of a Histogram?
As you can see in Viewgraph 3, a Histogram is made up of five parts:
1. Title: The title briefly describes the information that is contained in t
Histogram.
2. Horizontal or X-Axis : The horizontal or X-axis shows you the sca
values into which the measurements fit. These measurements are ggrouped into intervals to help you summarize large data sets. Individpoints are not displayed.
3. Bars: The bars have two important characteristicsheight and widt
height represents the number of times the values within an interval oThe width represents the length of the interval covered by the bar. It
same for all bars.
4. Vertical or Y-Axis : The vertical or Y-axis is the scale that shows y
number of times the values within an interval occurred. The number
is also referred to as "frequency."
5. Legend: The legend provides additional information that documents
the data came from and how the measurements were gathered.
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1 Title 2 Horizon tal / X-axis
3 Bars 4 Vertical / Y-axis
5 Legend
0 5 10 15 20 25 30 35 40 45 50 55 60
DAYS OF OPERATION PRIOR TO
FAILURE FOR AN HF RECEIVER
DAYS OF OPERATION
MEAN TIME BETWEEN FAILURE (IN DAYS) FOR R-1051 HF RECEIVER
Data taken at SIMA, Pearl Harbor, 15 May - 15 July 94
Parts of a Histogram
1
F
R
E
Q
UE
N
C
Y
4
5
0
20
40
60
80
100
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How is a Histogram constructed?
There are many different ways to organize data and build Histograms. You
safely use any of them as long as you follow the basic rules. In this moduleuse the nine-step approach (Viewgraphs 4 and 5) described on the followin
EXAMPLE: The following scenario will be used as an example to provide
we go through the process of building a Histogram step by step:
During sea trials, a ship conducted test firings of its MK 75,76mm gun. The ship fired 135 rounds at a target. An airbornespotter provided accurate rake data to assess the fall of shotboth long and short of the target. The ship computed what
constituted a hit for the test firing as:
From 60 yards short of the target
To 300 yards beyond the target
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Step 1 - Count number of data point
Step 2 - Summarize on a tally sheet
Step 3 - Compute the range
Step 4 - Determine number of interv
Step 5 - Compute interval width
Constructing a Histogram
Constructing a Histogram
Step 6 - Determine interval starting
points
Step 7 - Count number of points in
each interval
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Step 1 - Count the total number of data points you have listed. Sup
team collected data on the miss distance for the gunnery exercise descthe example. The data you collected was for the fall of shot both long athe target. The data are displayed in Viewgraph 6. Simply counting the
number of entries in the data set completes this step. In this example, t135 data points.
Step 2 - Summarize your data on a tally sheet. You need to summariz
data to make it easy to interpret. You can do this by constructing a tally
First, identify all the different values found in Viewgraph 6 (-160, -010
220, etc.). Organize these values from smallest to largest (-180, -12410).
Then, make a tally mark next to the value every time that value is prethe data set.
Alternatively, simply count the number of times each value is presendata set and enter that number next to the value, as shown in Viewg
This tally helped us organize 135 mixed numbers into a ranked sequencvalues. Moreover, we can see very easily the number of times that eacappeared in the data set. This data can be summarized even further by
intervals of values.
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HISTOGRAM VIEWG
Step 1 - Count the total number of data po
-180 30 190 380 330 140 160 270 10 - 9- 10 30 60 230 90 120 10 50 250 18
-130 220 170 130 - 50 - 80 180 100 110 20260 190 -100 150 210 140 -130 130 150 37160 180 240 260 - 20 - 80 30 80 240 13210 40 70 - 70 250 360 120 - 60 - 30 20
50 20 30 280 410 70 - 10 20 130 17140 220 - 40 290 90 100 - 30 340 20 8210 130 350 250 - 20 230 180 130 - 30 21-30 80 270 320 30 240 120 100 20 7
300 260 20 40 - 20 250 310 40 200 19
110 -30 50 240 180 50 130 200 280 6260 70 100 140 80 190 100 270 140 8110 130 120 30 70
TOTAL = 135
Number of yards long (+ data) and yards short (- data) that a gun crew missed its
How to Construct a Histogram
Step 2 - Summarize the data on a tally she
How to Construct a Histogram
DATA TALLY DATA TALLY DATA TALLY DATA TALLY DATA TA
- 180 3 90
- 130 2 100- 100 2 110
- 90 5 120
- 80 6 130
- 70 3 140
- 60 4 150
1
21
1
2
1
1
- 20
- 1010
20
30
40
50
2
53
4
8
5
2
190
200210
220
230
240
250
4
44
2
2
4
4
290
300310
320
330
340
350
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Step 3 -Compute the range for the data set. Compute the range by su
the smallest value in the data set from the largest value. The range repthe extent of the measurement scale covered by the data; it is always a number. The range for the data in Viewgraph 8 is 590 yards. This num
obtained by subtracting -180 from +410. The mathematical operation bdown in Viewgraph 8 is:
+410 - (-180) = 410 + 180 = 590
Remember that when you subtract a negative (-) number from another nbecomes a positive number.
Step 4 - Determine the number of intervals required . The number of
influences the pattern, shape, or spread of your Histogram. Use the foll
table (Viewgraph 9) to determine how many intervals (or bars on the bayou should use.
If you have this Use this number many data points: of intervals:
Less than 50 5 to 7
50 to 99 6 to 10
100 to 250 7 to 12
More than 250 10 to 20
For this example, 10 has been chosen as an appropriate number of inte
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HISTOGRAM VIEWG
Largest value = + 410 yards past target
Smallest value = - 180 yards short of targ
Range of values = 590 yards
Step 3 - Compute the range for the data s
How to Construct a Histogram
Calculation: + 410 - (- 180) = 410 + 180 = 5
IF YOU HAVE THIS
MANY DATA POINTS
USE THIS NUMBER
OF INTERVALS:
Less than 50
50 to 99
5 to 7 intervals
6 to 10 intervals
Step 4 - Determine the number of interva
required
How to Construct a Histogram
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Step 5 - Compute the interval wid th . To compute the interval width (Vie
10), divide the range (590) by the number of intervals (10). When com
interval width, you should round the data up to the next higher whole nu
come up with values that are convenient to use. For example, if the ranis 17, and you have decided to use 9 intervals, then your interval width i
You can round this up to 2.
In this example, you divide 590 yards by 10 intervals, which gives an int
width of 59. This means that the length of every interval is going to be 5
To facilitate later calculations, it is best to round off the value representinwidth of the intervals. In this case, we will use 60, rather than 59, as the
width.
Step 6 - Determine the starting point for each interval. Use the smal
point in your measurements as the starting point of the first interval. Th
point for the second interval is the sum of the smallest data point and thwidth. For example, if the smallest data point is -180, and the interval w
the starting point for the second interval is -120. Follow this procedure(Viewgraph 11) to determine all of the starting points (-180 + 60 = -120; = -60; etc.).
Step 7 - Count the number of poin ts that fall within each in terval. T
the data points that are equal to or greater than the starting value and
the ending value (also illustrated in Viewgraph 11). For example, if the
interval begins with -180 and ends with -120, all data points that are equgreater than -180, but still less than -120, will be counted in the first intein mind that EACH DATA POINT can appear in only one interval.
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HISTOGRAM VIEWG
59Interval
Width
Range
Number ofIntervals
=590
10
=
Use 10 for the
number of intervals
Use 10 for the
number of intervals
Round u
to 60
=
Step 5 - Compute the interval width
How to Construct a Histogram
INTERVAL
NUMBER
STARTING
VALUE
ENDING
VALUE
1
2
3
4
5
6
-180
-120
-060
000
060
120
INTERVAL
WIDTH
60
60
60
60
60
60
-120
-060
000
060
120
180
2 0
NUMBER OF
COUNTS
3
5
13
20
22
24
Step 6 - Determine the starting point of each inte
Step 7 - Count the number of points in each inte
How to Construct a Histogram
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Step 8 - Plot the data. A more precise and refined picture comes into vie
you plot your data (Viewgraph 12). You bring all of the previous steps towhen you construct the graph.
! The horizontal scale across the bottom of the graph contains the intewere calculated previously.
! The vertical scale contains the count or frequency of observations wof the intervals.
! A bar is drawn for the height of each interval. The bars look like colu
! The height is determined by the number of observations or percenta
total observations for each of the intervals.
! The Histogram may not be perfectly symmetrical. Variations will occ
yourself whether the picture is reasonable and logical, but be careful
your preconceived ideas influence your decisions unfairly.
Step 9 - Add the title and legend. A title and a legend provide the who,
when, where, and why (also illustrated in Viewgraph 12) that are importaunderstanding and interpreting the data. This additional information docthe nature of the data, where it came from, and when it was collected. T
may include such things as the sample size, the dates and times involve
collected the data, and identifiable equipment or work groups. It is impoinclude any information that helps clarify what the data describes.
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HISTOGRAM VIEWG
USS CROMMELIN (FFG-37), PACIFIC MISSILE FIRING RANGE, 135 BL&P ROUNDS/MOUNT 31, 2LEGEND:
Step 8 - Plot the data
Step 9 - Add the title and legend
How to Construct a Histogram
0
5
10
15
20
25
-180 -120 -060 000 060 120 180 240 300 360 420
TARGET
YARDS LONGYARDS SHORT
MISS DISTANCE FOR MK 75 GUN TEST FIRING
HITS
MISSESSHO
T
COUNT
MISSES
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How do we interpret a Histogram?
A Histogram provides a visual representation so you can see where most o
measurements are located and how spread out they are. Your Histogram mshow any of the following conditions (Viewgraph 13):
! Most of the data were on target, with very little variation from it, as inViewgraph 13A.
! Although some data were on target, many others were dispersed awthe target, as in Viewgraph 13B.
! Even when most of the data were close together, they were located target by a significant amount, as in Viewgraph 13C.
! The data were off target and widely dispersed, as in Viewgraph 13D
This information helps you see how well the process performed and how cowas. You may be thinking, "So what? How will this help me do my job bett
with the results of the process clearly depicted, we can find the answer to aquestion:
Did the process produce goods and services which are within specificatio
Looking at the Histogram, you can see, not only whether you were withinspecification limits, but also how close to the target you were (Viewgraph 14
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Target Target
Target Tar
Interpreting HistogramsLocation and Spread of Data
A
DC
B
Interpreting HistogramsIs Process Within Specif ication
Limits?
WITHIN LIMITS OUT OF SPEC
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Portraying your data in a Histogram enables you to check rapidly on the nuthe percentage, of defects produced during the time you collected data. Bu
you know whether the process was stable (Viewgraph 15), you wont be apredict whether future products will be within specification limits or determin
course of action to ensure that they are.
A Histogram can show you whether or not your process is producing produ
services that are within specification limits. To discover whether the processtable, and to predict whether it can continue to produce within spec limits,
to use a Control Chart (see the Control Chart module). Only after you havediscovered whether your process is in or out of control can you determine aappropriate course of actionto eliminate special causes of variation, or tofundamental changes to your process.
There are times when a Histogram may look unusual to you. It might have one peak, be discontinued, or be skewed, with one tail longer than the othe
shown in Viewgraph 16. In these circumstances, the people involved in the
should ask themselves whether it really is unusual. The Histogram may nosymmetrical, but you may find out that it should look the way it does. On t
hand, the shape may show you that something is wrong, that data from sev
sources were mixed, for example, or different measurement devices were uoperational definitions weren't applied. What is really important here is to a
jumping to conclusions without properly examining the alternatives.
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Interpreting HistogramsProcess Variation
Target
Day 1
Target
Day 2
Target
Day 3 Day 4
Target
Skewed
(not symmetrical)
Discontinued
Interpreting HistogramsCommon Histogram Shapes
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How can we practice what we've learned?
Two exercises are provided that will take you through the nine steps for dev
Histogram. On the four pages that follow the scenario for Exercise 1 you wset of blank worksheets (Viewgraphs 17 through 23) to use in working throuof the exercises in this module.
You will find a set of answer keys for Exercise 1 after the blank worksheetsExercise 2 after the description of its scenario. These answer keys represe
one possible set of answers. It's all right for you to choose an interval widthnumber of intervals that is different from those used in the answer keys. Evthough the shape of your Histogram may vary somewhat from the answer k
shape, it should be reasonably close unless you used a very different numbintervals.
EXERCISE 1: The source of data for the first exercise is the following sce
list of the data collected follows this description. Use the blank worksheetsViewgraphs 17 through 23 to do this exercise. You will find answer keys inViewgraphs 24 through 30.
Your corpsman is responsible for the semiannual PhysicalReadiness Test (PRT) screening forpercent body fat. Prior
to one PRT, the corpsman recorded the percent of body fatfor the 80 personnel assigned to the command. These are
the data collected:
PERCENT BODY FAT RECORDED
11 22 15 7 13 20 25 12 16
4 14 11 16 18 32 10 16 17
8 11 23 14 16 10 5 21 26
23 12 10 16 17 24 11 20 9
24 10 16 18 22 15 13 19 15
11 20 15 13 9 18 22 16 18
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Step 1 - Count the number of data pointWORKSHEET
TOTAL NUMBER =
WORKSHEET
Step 2 - Summarize the data on a tally she
VALUE TALLY VALUE TALLY VALUE TALLY VALUE TALLY VALUE T
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Largest value = _______________
Smallest value = _______________
________________________________________
Range of values = _______________
Step 3 - Compute the range for the data se
WORKSHEET
Step 4 - Determine the number of intervals
WORKSHEET
IF YOU HAVE THIS
MANY DATA POINTS
USE THIS NUMBER
OF INTERVALS:
Less than 50
50 to 99
5 to 7 intervals
6 to 10 intervals
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Step 5 - Compute the interval width
WORKSHEET
Interval
Width
Range
Number ofIntervals
= =
Round up
next high
whole num
=
Step 6 - Determine the starting point of each inteWORKSHEET
INTERVAL STARTING INTERVAL ENDING NUMBER
NUMBER VALUE WIDTH VALUE OF COUNTS
1
2
3
4
5
Step 7 - Count the number of points in each in ter
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Step 8 - Plot the data
Step 9 - Add ti tle and legend
WORKSHEET
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Step 1 - Count the number of data points
EXERCISE 1 ANSWER KEY
11 22 15 7 13 20 25 12 16 1
4 14 11 16 18 32 10 16 17 1
8 11 23 14 16 10 5 21 26 1
23 12 10 16 17 24 11 20 9 1
24 10 16 18 22 15 13 19 15 2
11 20 15 13 9 18 22 16 18
14 20 11 19 10 17 15 12 17 1
17 11 15 11 15 16 12 28 14 1
TOTAL = 80
Step 2 - Summarize the data on a tally she
EXERCISE 1 ANSWER KEY
0 0
1 02 0
3 0
4 1
5 1
6 0
%FAT NO. OF PERS
11 9
12 413 5
14 4
15 7
16 8
17 5
%FAT NO. OF PERS
22 3
23 224 3
25 1
26 1
27 0
28 1
%FAT NO. OF P
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HISTOGRAM VIEWGR
Step 3 - Compute the range for the data set
EXERCISE 1 ANSWER KEY
Largest value = 32 Percent body fat
Smallest value = 4 Percent body fat
_________________________________________
Range of values = 28 Percent body fat
Step 4 - Determine the number of intervals
EXERCISE 1 ANSWER KEY
Less than 50
50 to 99
5 to 7 intervals
6 to 10 intervals
IF YOU HAVE THIS
MANY DATA POINTS
USE THIS NUMBER
OF INTERVALS:
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EXERCISE 1 ANSWER KEYStep 6 - Determine the starting point of each inter
Step 7 - Count the number of points in each interv
INTERVAL STARTING INTERVAL ENDING NUMBER
NUMBER VALUE WIDTH VALUE OF COUNTS
1 4 + 4 8 3
2 8 + 4 12 20
3 12 + 4 16 20
4 16 + 4 20 20
5 20 + 4 24 10
HISTOGRAM VIEWG
3.5
Step 5 - Compute the interval width
EXERCISE 1 ANSWER KEY
Interval
Width
Range
Number ofIntervals
= =
Round u
to 4
=
28
8
Use 8 for the number
of intervals
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EXERCISE 1 ANSWER KEY
LEGEND: USS LEADER (MSO-490), 25 JUNE 94, ALL 80 PERSONNEL SAMPLED
4 8 12 16 20 24 28 32 360
JUNE 94 PRT PERCENT BODY FATSATISFACTORY % BODY FAT
PERCENT BODY FAT
NO.OFPERSONNEL
0
4
6
8
10
12
14
16
18
20
2
Step 8 - Plot the data
Step 9 - Add ti tle and legend
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EXERCISE 2: The source of data for the second exercise is the followin
A listing of the data collected follows this description. Use the blank work
Viewgraphs 17 through 23 to do this exercise. You will find answer keys Viewgraphs 31 through 37.
A Marine Corps small arms instructor was performing ananalysis of 9 mm pistol marksmanship scores to improve
training methods. For every class of 25, the instructorrecorded the scores for each student who occupied thefirst four firing positions at the small arms range. The
instructor then averaged the scores for each class,maintaining a database on 105 classes. These are thedata collected:
AVERAGE SMALL ARMS SCORES
160 190 155 300 280 185 250 285 200
175 190 210 225 275 240 170 185 215
270 265 255 235 170 175 185 195 200
180 245 270 200 200 220 265 270 250
255 180 260 240 245 170 205 260 215
255 245 210 225 225 235 230 230 195
230 255 235 195 220 210 235 240 200
195 235 230 215 225 235 225 200 245
220 215 225 250 220 245 195 235 225
210 240 215 230 220 225 200 235 215
220 230 225 215 225
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160 190 155 300 280 185 250 285 200 16
175 190 210 225 275 240 170 185 215 22
270 265 255 235 170 175 185 195 200 26
180 245 270 200 200 220 265 270 250 23255 180 260 240 245 170 205 260 215 18
255 245 210 225 225 235 230 230 195 22
230 255 235 195 220 210 235 240 200 22
195 235 230 215 225 235 225 200 245 23
220 215 225 250 220 245 195 235 225 23
210 240 215 230 220 225 200 235 215 24
220 230 225 215 225
Step 1 - Count the number of data points
TOTAL = 105
EXERCISE 2 ANSWER KEY
155 1
160 1
165 1
170 3
175 2
180 2
205 1
210 4
215 7
220 8
225 11
230 9
255 4
260 3
265 2
270 3
275 1
280 1
Step 2 - Summarize the data on a tally sheetEXERCISE 2 ANSWER KEY
SCORE TALLY SCORE TALLY SCORE TALLY
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Step 3 - Compute the range for the data se
EXERCISE 2 ANSWER KEY
Largest value = 300 Points
Smallest value = 155 Points
__________________________________
Range of values = 145 Points
Step 4 - Determine the number of interval
EXERCISE 2 ANSWER KEY
Less than 50
50 to 99
5 to 7 intervals
6 to 10 intervals
IF YOU HAVE THIS
MANY DATA POINTS
USE THIS NUMBER
OF INTERVALS:
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EXERCISE 2 ANSWER KEY
Step 6 - Determine the starting point of each interv
Step 7 - Count the number of points in each interv
INTERVAL STARTING INTERVAL ENDING NUMBER
NUMBER VALUE WIDTH VALUE OF COUNTS
1 155 + 15 170 3
2 170 + 15 185 7
3 185 + 15 200 11
4 200 + 15 215 12
5 215 + 15 230 26
HISTOGRAM VIEWGR
14.5
Step 5 - Compute the interval width
EXERCISE 2 ANSWER KEY
Interval
Width
Range
Number ofIntervals
= =
Round up
to 15
=
145
10
Use 10 for the number
of intervals
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155 170 185 200 215 230 245 260 275 290 300
0
5
10
15
20
25
30
SCORES
NO.OFPERSONN
EL
MARKSMANSHIP SCORES FOR 9mm PISTOL
LEGEND: MCBH KANEOHE BAY, HI; AVERAGE OF 4 SCORES PER CLASS, 105 CLASSES, 1 JUNE 94 - 15
EXERCISE 2 ANSWER KEY
Step 9 - Add title and legend
Step 8 - Plot the data
p
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p
REFERENCES:
1. Brassard, M. (1988). The Memory Jogger, A Pocket Guide of Tools forContinuous Improvement, pp. 36 - 43. Methuen, MA: GOAL/QPC.
2. Department of the Navy (November 1992), Fundamentals of Total QuaLeadership (Instructor Guide), pp. 6-44 - 6-47. San Diego, CA: Navy PResearch and Development Center.
3. Department of the Navy (September 1993). Systems Approach to ProcImprovement (Instructor Guide), pp. 10-17 - 10-38. San Diego, CA: OU
Quality Leadership Office and Navy Personnel Research and DevelopmCenter.
4. Naval Medical Quality Institute (Undated). Total Quality Leader's CoursGuide), pp. U-26 - U-28. Bethesda, MD.
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HISTOGRAM
VIEWGRAPH1
W
hatIsa
Histogram?
Abargra
phthatshowsthedistributionofdata
Asnapsh
otofdatatak
enfromapro
cess
0
5
10
15
20
25
30
35
40
45
50
55
60
020
40
60
80
100
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HISTOGRAM
VIEWGRAPH2
When
AreHistograms
Used?
Summarizelargedatasetsgrap
hically
Compare
measurem
entstospe
cifications
Communicateinform
ationtothe
team
Assistindecisionmaking
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HISTOGRAM
VIEWGRAPH3
1
Title
2Horizontal/X-axis
3
Bars
4
Vertical/Y-axis
5
Legend
0
5
10
1
5
20
25
30
35
40
45
50
55
60
DAY
SOF
OPERATIONPRIORT
O
FAILUREF
ORANH
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OPE
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URE
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ar
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ay-1
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0 204
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80
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HISTOGRAM
VIEWGRAPH4
Step1-
Coun
tn
um
ber
of
da
tapoin
ts
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ariz
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etermin
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num
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terv
al
s
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Computeinterv
alwi
dth
Cons
tructing
aHisto
gram
-
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HISTOGRAM
VIEWGRAPH5
Cons
tructing
aHisto
gram
Step6-
Determin
einterv
al
startin
g
points
Step7-
Coun
tn
u
mber
of
pointsin
eachin
te
rval
Step8-
Plotthed
ata
Step9-
Addtitleandle
gen
d
-
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HISTOGRAM
VIEWGRAPH6
Step1-Cou
ntthetotalnumberofdatapoints
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40
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How
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H
-
8/8/2019 6811944 Histogram VG
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HISTOGRAM
VIEWGRAPH7
S
tep2-Sum
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How
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am
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200
210
220
230
240
250
260
270
280
4442244432
290
300
310
320
330
340
350
360
370
380
410
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H
-
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HISTOGRAM
VIEWGRAPH8
L
argestvalu
e
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sttarget
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mallestvalue
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angeofva
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C
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H
-
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HISTOGRAM
VIEWGRAPH9
IFYOUHA
VETHIS
MANYDATA
POINTS
USETHISNUM
BER
OFINTERVA
LS:
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99
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Step4-Determinethenumbero
fintervals
required
How
toCon
stru
ctaHis
togr
am
H
-
8/8/2019 6811944 Histogram VG
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ISTOGRAM
VIEWGRAPH10
59
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terval
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idth
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lwidth
How
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structaHis
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am
HI
-
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STOGRAM
VIEWGRAPH11
INTERVAL
NUMBER
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TING
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UE
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VAL
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60
60
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BER
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ater
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p7-Countthenumber
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How
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STOGRAM
VIEWGRAPH12
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How
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STOGRAM
VIEWGRAPH13
Targ
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gram
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A
D
C
B
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-
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STOGRAM
VIEWGRAPH14
Interpre
tingHisto
gram
s
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ssWith
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et
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ow
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ationlimit
HIST
-
8/8/2019 6811944 Histogram VG
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TOGRAM
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tingHisto
gram
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rocessVariation
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et
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Day
2
T
arg
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Day
4
T
arg
e
t
HIST
-
8/8/2019 6811944 Histogram VG
50/71
TOGRAM
VIEWGRAPH16
Skew
ed
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etrical)
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tinued
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tingHisto
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gram
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HIST
-
8/8/2019 6811944 Histogram VG
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TOGRAM
VIEWGRAPH17
Step1-Co
untthenu
mberofda
tapoints
WORK
S
HEET
TOTALN
UMBER
=
HIST
-
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OGRAM
VIEWGRAPH18
WORK
S
HEET
S
tep2-Sum
marizethedataona
tallysheet
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ETALLY
VALUE
TALLY
VALUE
TALLY
VALUE
TALL
YVALUE
TALLY
HISTO
-
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OGRAM
VIEWGRAPH19
Largestval
ue
=
__________
_____
Smallestva
lue
=
__________
_____
__________
____________
__________________
Rangeofvalues
=
__________
_____
S
tep3-Com
putetherangeforth
edataset
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HISTO
-
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OGRAM
VIEWGRAPH20
S
tep4-Det
erminethe
numberofintervals
WORK
S
HEET
IFYOUHAV
ETHIS
MANYDATA
POINTS
USETHISNU
MBER
OFINTERV
ALS:
Lessthan
50
50to
99
100to2
50
More
than2
50
5
to
7
in
tervals
6
to
10
in
tervals
7
to
12
in
tervals
10
to
20
in
tervals
HISTO
-
8/8/2019 6811944 Histogram VG
55/71
OGRAM
VIEWGRAPH21
Step5-Computetheintervalwidth
WORK
SHEET
Interval
W
idth
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ge
Num
ber
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Interv
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=
=Roun
dupto
nex
thigh
er
wholen
um
ber
=
HISTO
St
St
-
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56/71
OGRAM
VIEWGRAPH22
tep
6-Determinethestartingpointofeachinterva
l
WORK
S
HEET
INTERVALSTARTING
INTERVAL
ENDING
NUMBER
NUMBER
V
ALUE
WIDTH
VALUE
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OUNTS
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tep7-Countthenumbero
fpointsine
achinterval
HISTOG
-
8/8/2019 6811944 Histogram VG
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GRAM
VIEWGRAPH23
Step8-Plotth
edata
Step9-Addtitleandlege
nd
WORK
SHEET
HISTOG
-
8/8/2019 6811944 Histogram VG
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GRAM
VIEWGRAPH24
Step1-Countthenum
berofdatapoints
EXE
RCISE1ANSWERKE
Y
11
22
15
7
13
20
25
12
16
19
4
14
11
16
18
32
10
16
17
10
8
11
23
14
16
10
5
21
26
10
23
12
10
16
17
24
11
20
9
13
24
10
16
18
22
15
13
19
15
24
11
20
15
13
9
18
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18
9
14
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11
19
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17
15
12
17
11
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11
15
11
15
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28
14
13
TOTA
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HISTOG F
-
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GRAM
VIEWGRAPH25
St
ep2-Summarizethe
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llysheet
EXE
RCISE1ANSWERKE
Y
0
0
1
0
2
0
3
0
4
1
5
1
6
0
7
1
8
1
9
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10
7
%FAT
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OFPER
S
11
9
12
4
13
5
14
4
15
7
16
8
17
5
18
4
19
3
20
4
21
1
%
FAT
NO.
O
FPER
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22
3
23
2
24
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25
1
26
1
27
0
28
1
29
0
30
0
31
0
32
1
%
FAT
NO.
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S
HISTOG
-
8/8/2019 6811944 Histogram VG
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GRAM
VIEWGRAPH26
S
tep3-Com
putethera
ngeforthe
dataset
EXE
RCISE1ANSWERKE
Y
Largestvalu
e
=
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en
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t
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t
___________
____________
____________
______
Rangeofva
lues
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erc
en
tbodyfa
t
HISTOG
-
8/8/2019 6811944 Histogram VG
61/71
RAM
VIEWGRAPH27
S
tep4-Dete
rminethenumberofintervals
EXE
RCISE1ANSWERKE
Y
Lessthan
50
50to99
100to2
50
More
than2
50
5
to
7
intervals
6
to
10
intervals
7
to
12
intervals
10
to
20
intervals
IFYOUHAV
ETHIS
MANYDATAPOINTS
USETHISNU
MBER
OFINTERV
ALS:
HISTOGR
-
8/8/2019 6811944 Histogram VG
62/71
RAM
VIEWGRAPH28
3.5
Step5-Computeth
eintervalw
idth
EXE
RCISE1ANSWERKE
Y
Interval
W
idth
Ran
ge
Number
of
Interv
als
=
=Roun
dup
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=
288
Use8for
thenum
ber
ofin
te
rvals
HISTOGR
Ste
Ste
-
8/8/2019 6811944 Histogram VG
63/71
RAM
VIEWGRAPH29
EXE
RCISE1ANSWERKE
Y
Equal
toor
gre
ater
than
theSTARTIN
GVAL
UE
Butle
ssthan
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GVA
LUE
ep
6-Determinethestartin
gpointofeachinterval
ep
7-Countth
enumberofpointsinea
chinterval
INTERVAL
STAR
TING
INTERVAL
ENDIN
G
NU
MBER
NUMBER
VAL
UE
WIDTH
VAL
UE
OF
C
OUNT
S
1
4
+4
8
3
2
8
+4
12
20
3
1
2
+4
16
20
4
1
6
+4
20
20
5
2
0
+4
24
10
6
2
4
+4
28
5
7
2
8
+4
32
1
8
3
2
+4
36
1
HISTOGR
-
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RAM
VIEWGRAPH30
EXE
RCISE1A
NSWERKE
Y
LE
GEND:
USSLEAD
ER(MSO-4
90),2
5JUNE
94
,ALL
80PER
SONNEL
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PLED
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8
12
16
20
24
28
32
36
0
JUNE
94PRTPER
CENTB
ODYFAT
SATISFA
CT
ORY
%
BOD
YFAT
PER
CENTB
ODY
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NO. OF PERSONNEL
0 4 6 81
012
14
16
18
202
Step8-Plotthedata
Step9-Addtitle
andlegend
HISTOGRA
160
17
527
01
80
255
255
230
195
22
021
022
0
-
8/8/2019 6811944 Histogram VG
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AM
VIEWGRAPH31
0
190
155
300
280
18
5
250
285
200
165
5
190
21
0
225
27
5
24
0
17
0
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21
5
22
0
0
265
255
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17
0
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5
185
195
200
260
0
24
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27
0
200
200
22
0
265
27
0
250
230
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180
260
240
24
5
17
0
205
260
21
5
185
5
24
5
21
0
225
22
5
23
5
230
230
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22
0
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200
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235
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23
5
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5
22
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250
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24
5
195
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230
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S
tep1-Cou
ntthenum
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EXERCISE2ANSWERKE
Y
HISTOGRA
S
-
8/8/2019 6811944 Histogram VG
66/71
AM
VIEWGRAPH32
155
1
160
1
165
1
170
3
175
2
180
2
185
4
190
2
195
5
200
7
205
1
21
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4
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7
22
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8
22
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1
1
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9
235
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24
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250
3
255
4
260
3
265
2
27
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3
27
5
1
280
1
285
1
290
0
295
0
300
1
tep2-Summ
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ataonata
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EXERCISE2ANSWERKE
Y
SCORE
TALLY
SCORE
TALLY
SCOR
ETALLY
HISTOGRA
St
-
8/8/2019 6811944 Histogram VG
67/71
AM
VIEWGRAPH33
tep3-Computetheran
geforthe
dataset
EXE
RCISE2ANSWERKE
Y
Largest
value
=
300P
oin
ts
Smallestvalue
=
155P
oin
ts
________________________________
__
Rangeo
fvalues
=
14
5P
oin
ts
HISTOGRA S
-
8/8/2019 6811944 Histogram VG
68/71
AM
VIEWGRAPH34
S
tep4-Dete
rminethen
umberofi
ntervals
EXE
RCISE2ANSWERKE
Y
Lessthan
50
50to99
100to2
50
More
than2
50
5
to
7
inte
rvals
6
to
10
inte
rvals
7
to
12
inte
rvals
10
to
20
inte
rvals
IFYOUHAVETHIS
MANYDATAPOINTS
USETHISNUMBER
OFINTERVALS:
HISTOGRAM
InW
-
8/8/2019 6811944 Histogram VG
69/71
M
VIEWGRAPH35
14.5
Step5-C
omputeth
eintervalw
idth
EXE
RCISE2ANSWERKE
Y
nterval
W
idth
Ran
ge
Number
of
Interv
als
=
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dup
to1
5
=
14
51
0
Use10forth
enumber
ofintervals
HISTOGRAM
Step
Ste
-
8/8/2019 6811944 Histogram VG
70/71
M
VIEWGRAPH36
EXE
RCISE2ANSWERKE
Y
p
6-Determin
ethestartin
gpointofea
chinterval
p
7-Countth
enumberof
pointsinea
chinterval
Equal
toor
gre
ater
than
theSTARTIN
GVAL
UE
Butle
ssthan
theENDIN
GVAL
UE
INTERVAL
START
ING
INTERVAL
ENDING
NU
MBER
NUMBER
VAL
UE
WIDTH
VALUE
OFCOUNTS
1
15
5
+15
170
3
2
17
0
+15
185
7
3
18
5
+15
200
11
4
20
0
+15
215
12
5
21
5
+15
230
26
6
23
0
+15
245
22
7
24
5
+15
260
12
8
26
0
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275
8
9
27
5
+15
290
3
10
29
0
+15
300
1
HISTOGRAM
NO OF PERSONNEL
LE
GEND
-
8/8/2019 6811944 Histogram VG
71/71
M
VIEWGRAPH37
155
17
0
185
200
21
5
230
24
5
260
27
5
290
300
0 5 10 15 20 25 30
SCORES
NO. OF PERSONNEL
MARK
SMA
NSHIP
SCORE
SFOR
9mmPIS
TOL
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CBHKANE
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EXERCISE2AN
SWERKE
Y
Step9-Addtitle
andlegend
Step8-Plotthe
data