This document provides instructions and examples for constructing different types of graphs used in geography:
1) Age-sex pyramids show population structure broken down by age and gender. Procedures and an example are given for constructing one.
2) Compound bar graphs subdivide bars to show component parts. Procedures and an example construction are outlined.
3) Dot maps show distributions using dots of varying size. Procedures, advantages, disadvantages and a worked example are described.
4) Simple line graphs show relationships between two variables over time. Construction procedures, advantages and disadvantages are summarized.
5) Flow line maps illustrate movement between locations using line thickness. Procedures, an example, advantages
1. SAINT AUGUSTINE UNIVERSITY OF TANZANIA
BUKOBA CENTRE
FACULTY: EDUCATION
DEPARTMENT: GEOGRAPHY
COURSE TITLE RESEARCH METHODS IN GEOGRAPHY
COURSE CODE: GE 249
NAME OF INSTRUCTOR: MR, BASHEKA J. J
WORK: GROUP ASSIGNMENT
DATE OF SUBMISSION: March, 25th
2014.
GROUP NAME SOPHISTS B
PARTICIPANTS
NO NAME REG NO SIGNATURE
1 KIBIRITI JOSEPH BAED II 41546
2 LAMECK MHOJA BAED II 41554
3 MADUHU GONZI BAED II 41573
4 MAPESA NESTORY BAED II 41584
5 MATHIAS BHOKE BAED II 41594
6 MSILA BHOKE BAED II 40971
QuestionTask
Age and Sex Pyramid Define concepts
Compound Bar graph State procedures for construction
Dot Maps What are the Advantages
Simple Line Graph What are the disadvantages
Flow Line Maps Use Hypothetical data to construct
2. 1. Age and Sex pyramid;
Are the type of graph which shows demographic study in age and sex that show the
structure of population in selected country. Age and Sex pyramid displays the percentage or
actual amount of a population broken down by the gender and age.
Types of Age and Sex pyramid;
There are three key types of population pyramid, which are Rapid growth, Slow growth and
Negative growth
i/ Rapid Growth
This shows a triangle shaped pyramid and reflects a high growth rate of about 2.1% annually.
Example is in Mexico 2000.
ii/ Slow growth;
This population grown at the rate of about 1.7% annually. This growth rate is reflected in the
more square like structure of the pyramid. Example in Iceland 2000.
iii/ Negative growth;
This is a negative growth in a country continues population is reduced. A population can shrink
due to a low birth rate and stable birth rate. Common example is in Japan 2000. It is experiencing
a period of negative growth of -0.1%
Examples of figures are illustrated below to the next page
3.
4. Procedures to construct Age and Sex Pyramid graph;
i/ To construct Vertical and horizontal axes . While horizontal axis is scaled either in absolute
value or percentage and vertical axis occupies independent variable.
ii/ To select the methods to use. Either percentage method or absolute method used in
modification of horizontal scale that could produce different shape of population (female and
male).
iii/ Male usually presented in the left and female in the right. This must be indicated in graph.
iv/The male and female section must be separated in space provided with vertical scale in terms
of Age group.
v/ Horizontal scale must be printed in both sides (female and male)
vi/ When used for purpose of comparison, the graph must be drawn in the same scale.
vii/ Care must be taken in choosing the scale so as to avoid narrow and elongated or one that is
too wide or flat.
Advantages of Age and Sex pyramid;
i/ It gives clear picture or summary of population composition.
ii/ It is used to make comparison of population in terms of time or location.
iii/ It is used to represent Age and Sex structure of the population which is dependent on birth
and death rates of population over time.
iv/ It is used to represent growth of the total population over a period of years.Example in Census
enumeration.
Disadvantages of Age and Sex pyramid;
i/ It consumes much time to construct since it comprise different age groups and sex
ii/ It leads exaggeration in choosing scales ( vertical and horizontal) which can produce narrow
or elongated graph.
iii/ It is difficult to construct because it uses complex calculation , for instance when the
percentage method is used.
5. Example;
The given data of Tanzania, then produce a neat Age and Sex graph (population pyramid) based
on the data in (000)
Age (yrs) Male Female
0--4 43200 41000
5--9 38800 37200
10--14 33500 32500
15--19 28900 27400
20--24 26000 22300
25--29 25000 19900
30--34 19900 18500
35--39 18800 16000
40--44 12000 12000
45--49 9900 10000
50--54 8800 8900
55--59 6500 8800
60--64 6000 8700
65--69 5500 8500
70--74 5000 7500
75--79 4200 7000
80--84 4000 6800
85--89 3700 6000
90--94 2000 4000
95--99 900 2200
100+
Solution; Scale; H.S 1cm = 10000 mil (000)
V.S 1cm = x group age
6. AGE AND SEX PYRAMID GRAPH IN TANZANIA 2013
2: COMPOUND BAR GRAPHS;
Are the graphs which drawn by sub-dividing one bar into its component parts; The total length of
the bar represent the total value of the component parts shown as sub- divisions.
Procedures to construct Compound Bar Graphs;
i/ Identify the title of given data
ii/ Add or cumulate the value data in specific period and individuals to get the total length of bar.
It help to estimate the scale.
iii/Choose scales, the vertical and horizontal line in term of absolute values or percentages
iv/Draw the Compound bar vertically or horizontally bars should be drawn vertically and year
bars drawn horizontally.
v/When drawing vertical, bars may be sub- divided in descending order of size ( The smallest at
the top largest value at bottom).
vi/Colouring or shading of the Components to improves the appearance and assist interpretation.
That Colouring or shading must indicate the same components over period of time.
7. Example crop production during 1998-2001 in tons
Crop 1998 1999 2000 2001
Maize 200 260 275 280
Tea 100 200 180 260
Coffee 150 220 200 170
Total 450 680 655 710
Solution;
A COMPOUND BAR GRAPH FOR YEARS 1998-2001
A Cumulative Table
Year 1998 1999 2000 2001
maize 200 260 275 280
tea 300 460 455 540
coffee 450 680 655 710
Scale;
V.S 1cm to 100 tonnes
H.S 2cm to 1year.
8. Advantages of Compound bar Graph;
i/ It facilitates easy comparison of data or production
ii/ It is easy to interpret when data provided
iii/ It shows good impressive since different colours are used
iv/ It saves space in presentation
v/ It is easy to construct
Disadvantages of Compound bar Graph;
i/ It involves tedious Calculations when estimating scale
ii/ It is not easy to see the trend of individual variable when they are too many and vary by great
margins.
iii/ They can cause confusion if proper care is not taken in data presentation
iv/ Colouring and shading do not provide actual results when many data are involved.
0
100
200
300
400
500
600
700
800
1998 1999 2000 2001
A COMPOUND BAR GRAPH FOR THE YEAR 1998- 2001
COFFEE
TEA
MAIZE
9. 3. DOT MAPS;
This refers to the maps which normally shows the distribution statistical information through the
use of dots. There are three considerations under dot maps which are;
I/Dot size;This refers to the size of dot to be drawn,
Ii/dot value; This refers to the number of values which each dot represent a base map. Example
1dot = 1000 students
iii/dot location; It is used to locate the correct position of dot in the base map.
Procedures to construct dots maps;
i/You should have the base maps
ii/Find the dot value example 1dot = 200 people in the class
iii/ Determine the dot size
iv/Drawing the dos.
v/ Back to your topographical map and identify title, key and scale
Advantages of Dots maps;
i/It is easy to be interpreted quantitation
ii/ They show good visual impression for comparison purpose
iii/ They are easy to draw if the calculation is already calculated
iv/ More than one item can be shown by using different colours of dots. Example people and
animals.
v/ It has variety of uses example showing volume and quantity
vi/ Simple and easy to construct so long the dot value can be computed
vii/ Different tribes can be shown in a region
Disadvantages of Dots maps;
i/ Faults in construction as dot value can be too low or too high
10. ii/If topographical map is not given, distribution of dots in the map gives wrong impression as
one cannot easily know the location of physical barriers.
iii/ With large dot value distributions cannot be shown accurately .
iv/ It is difficult to make dots of the same size if you do not have a special dot pen
v/ Requires careful selection of dot scale to get correct picture
vi/ It is time consuming as it involves trial and error in finding dot value.
Example;
Draw a dot map to show distribution of goats in Dodoma region in 1980
District Goats
Kongwa 10,000
Kondoa 30,000
Mpwapwa 20,000
Dodoma 50,000
Solution;
Thus in trial and error map you may use a scale of one dot to 1000 goats
District Dots
Kongwa 10000/1000 = 10
Kondoa 30,000/1000 = 30
Mpwapwa 20,000/1000 = 20
Dodoma 50,000/1000 = 50
11. Dot map: Distribution of Goats in Dodoma region, 1980
1dot represents 1000 Goats
Dodoma= 50,000
Kondoa= 30,000
Mpwapwa = 20,000
Kongwa = 10,000
4 .SIMPLE LINE GRAPH
Is it used to portray the relationship between two variables for example tonnage of maize
production over time.
Construction procedures;
i/ Draw a horizontal axis and two vertical axes one at each end of the horizontal axis
ii/ Mark an approximate scale for both the horizontal axis that is time in months or year and
vertical axis which is value or amount example tone.
Iii/ Use dots when plotting the time against on the graph and join the dots to produce a line
graph, either using a free hand line segment.
v/ The line graph is completed by giving it a suitable title,
Example Maize production in Tanzania; 1990-1994( in 000`s tons)
YEAR 1990 1991 1992 1993 1994
PRODUCTION
IN (000`S)
200 250 275 280 285
12. Scale: V.S= 2cm to 50,000 tones
H. S= 2cm to 1 year
300
250
200
150
1990 1991 1992 1993 1994
Time in years
Key;
___ Maize
Advantages of simple line graph;
i/ Easy to construct and interpret
ii/ Enables ones to easily compare variations in the relationship between variables
iii/ Does not involves lengthy and tedious calculations.
Iv/ The trend of the relationship can easily seen
v/ Exact value can easily be estimated from the graph
Disadvantagesof simple line graph;
i/ It gives the misleading impression that the pattern or trend is constant.
ii/ The causes of illustrated relationship cannot be established from the graph.
13. 5. FLOW LINE MAP
Flow line maps also are called Flow chart. Flow line maps can be defined as a chart that illustrate
the movement of information and products between different locations. Also it can show flow/
movement or migration data of people, animals, products or object of concern in given
geographical location. This movement is observed at a specific check point along the route or
data can be obtained at the end station such as port, bus station or airport.When volume of flows
is shown by lines whose width varies in proportion to the number of goods, people travelling
along the route.
Steps/ Procedures/ Methods of Construction Flow line Map;
i/Draw a base map of the route network each route being shown by fine single pencil line traced
from the original map called reduced or enlarged if necessary.
ii/ Mark in pencil all the check points or each and flow values against each point
iii/ Choose a suitable scale for the flow line map. This usually depends on the map size, the data
value range and the route network density simple direct proportion between quantity to be
represented and width of the flow line taken. This help to avoid very thin line to be used.
Sometimes square root or logarithms are used for very large values.
iv/ Divide each flow line scale value by 2. Then with point of the compasses or dividers on the
traced road, the route. Join the mark points with a pencil line and do the same for other size of
the route .Angular joint should be drawn at each junction neatly.
v/ Outline the key flow line in the ink and shade them lightly in colour.
vi/ Insert the key for your flow line map together with the heading of the map.
Example ; Read careful the data below and answer the question follows as instructed.
Town Tones
Arusha 15117
Dodoma 25000
Mwanza 12400
Songea 11013
Iringa 13000
Dar es Salaam 40000
Draw the flow line map to represent the movements of goods in some regions of Tanzania to
Dar es Salaam Solution;
14. Town Tones Rounded the
figure
Scale 1mm=4000
tones
Divided by 2
Arusha 15117 15000 15000/4000=3.75mm 4mm/2= 2mm
Dodoma 25000 25000 25000/4000=
6.25mm
6mm/2=3mm
Mwanza 12400 12000 12000/4000=3mm 3mm/2= 1.5mm
Songea 11013 11000 11000/4000=2.75mm 3mm/2=1.5mm
Dar es Salaam 40000 40000 40000/4000= 10mm 10mm/2=5mm
THE FLOW LINE MAP SHOWING THE MOVEMENT OF GOODS IN SOME REGION IN
TANZANIA TO DAR ES SALAAM
UGANDA KENYA
KEY; ZAMBIA
Mwanza to Dodoma
Arusha to dodoma
Dodoma to Dar es Salaam
Songea to Dodoma MOZAMBIQUE
15. Advantages of Flow line maps;
1. The only way which can show movement of goods
2. It is easy to draw and interpret once the scale has being considered
3. They provide a convenient visual way of illustrating movement.
4. It can show direction of two traffics such as import and exports at the same time.
5.It is good in showing problem of movement example traffic congestion
6. It gives good visual impression which facilitates interpretation.
7. The method allows other statistical information to be added on the map.
Disadvantages of Flow line maps;
1. Choice of scale and calculation is not easy
2. It is not easy to present more than one item instead of traffic only.
3. It is difficult to present low volume of the item in question
4. Real figures are not shown on the map so it is difficult to know the actual volume of the item
being represented.
5. It may give misleading information as it assumes that all reluctes leaving a point will arrive at
the same ending point.
6. It is very difficult to maintain the width of the flow paths in cases where the flow line has
many bend
16. REFERENCES
Cothari C.R. (1990), Research Methodology, Methods and Techniques,
Weley Eastern, New Delhi
Pritchat J. M (1984) Practical Geography for Africa, Hong Kong