ASSIGNMENT GOAL:
To understand how to calculate, graphically represent and interpret various measures of population.
LEARNING OUTCOMES:
- After completing this assignment you will be able to:
- Understand population structure and composition
- Construct and interpret population pyramids
- Calculate sex and dependency ratios for different populations
- Use population statistics to compare population groups
BACKGROUND:
This assignment is based on Module 3 and Module 4 of the Human Geography Lab Manual.
Measuring Population Growth:
Introduction:
At its core, demography is a specialized discipline which studies human populations and their basic characteristics. Among other topics, demographers ask questions about the composition (age, ethnicity, and gender) and size of the population, how quickly or slowly it is growing, and how its numbers are affected by births and deaths (Beaujot and Kerr, 2004, p. 3). They may also focus on inherently geographical questions, such as differences in the density of populations between regions (spatial variation), and the magnitude and impact of, and rationale for, migration.
Population geography is a branch of geography that is related to demography in that it also aims to understand and measure certain characteristics of human populations. However, it does so with a particular focus on the variations in these characteristics across space or, as in the case of migration, on how these processes play out across the earth’s surface and over time. Population geographers are also interested in how local conditions at a given place affect local demographic variables, and vice versa.
The immediate subject of interest, and consequently the approach, of the population geographer can vary considerably, from the basic to the complex. Thus, geographer Wilbur Zelinsky identified three approaches, each with increasing complexity (Zelinsky, 1966). At the most basic level, a researcher would simply describe the population at a given location in terms of numbers and other demographic characteristics. More advanced studies would identify and explain the observed spatial patterns of these phenomena. Finally, Zelinsky noted that, at its most advanced, population geography seeks to understand the differences in population that can be observed across space, and the contribution to those differences made by local characteristics or phenomena’ (pp. 5-6).
In this assignment you will explore population geography through a series of basic exercises, designed to introduce you to a few of the concepts and techniques employed in this branch of geography. To complete this assignment you will create, assess and compare population pyramids; and evaluate the age and sex composition of a population.
Key Concepts:
- population pyramid age cohorts sex ratio
- dependency ratio youth dependency ratio old-age dependency ratio
- population structures
Background Readings:
Norton, 2009 Human Geography, Chapter 4
Adams and Taylor, 2009 Peterborough and the Kawarthas, Chapters 1 “The Regional Setting” & Chapter 8, “The City of Peterborough”
1. Population Pyramids:
In this section you will construct a population pyramid based on current census data for Curve Lake First Nations community. You will then analyze and compare this pyramid to those for the City of Peterborough and the Province of Ontario (as found in Chapter 8, Peterborough and the Kawarthas) to determine whether or not the populations of these areas share the same profile.
A population pyramid is a type of chart, shaped somewhat like a pyramid, employed by demographers and others to depict graphically the structure of a population. There is more information on population pyramids in your text (Norton 2009), along with examples.
Essentially, a population pyramid is composed of two horizontal bar charts, one each for females and males, placed back to back, with percentage of the total population (or number of individuals) measured out along the horizontal axis, and age along the vertical axis. This provides a total view of the age and sex structure at a given moment in time, but it also records the demographic impact of historical events, such as mortality from past wars, or past trends, such as culturally induced increases or declines in the birth rate. By evaluating the shape of these pyramids, we can determine the general trends of the population, including whether it is in a period of growth or decline, or whether it is aging or growing younger, as well as the ratio of males to females for any given age group (cohort).
Curve Lake Population Pyramid:
The Curve Lake Anishinaabe (Ojibway) community is located roughly 25 km north of the City of Peterborough. Further information on this community can be found on the Curve Lake First Nation website (https://curvelakefirstnation.ca/about-us/).
a. Begin by constructing a pyramid for Curve Lake First Nation for the year 2006, using the data provided in the table on the following page. It is possible to construct this either manually (by hand), on the graph paper provided for instance, or digitally, using a program such as Excel. Our preference is that you use spreadsheet software.
For this part of the exercise you should follow a few basic guidelines:
Use five-year age groups, or cohorts. Note that the data have already been aggregated into these cohorts.
The upper age cohort will be 70+.
Males will be on the left and females on the right.
Place the vertical scale (y-axis) on the left side of the pyramid, rather than in the middle.
For the horizontal scale (x-axis) measure the increments as percentages of the total population.
Curve Lake First Nation Population, 2006
Age
Cohort
Male Female
0-4 25 25
5 to 9 35 35
10 to 14 50 45
15 to 19 45 30
20 to 24 35 30
25 to 29 20 20
30 to 34 30 30
35 to 39 25 50
40 to 44 45 40
Age
Cohort
Male Female
45 to 49 35 50
50 to 54 40 45
55 to 59 35 40
60 to 64 30 45
65 to 69 30 25
70 to 74 10 15
75 to 79 5 5
80 to 84 10 5
Source: Statistics Canada, 2006 Community Profile, Curve Lake
Be sure to attach a printout of your pyramid to your assignment. Label it
1.
a. Curve Lake population pyramid
After completing this pyramid, answer the following questions:
b. Describe the population pyramids for Curve Lake, the City of Peterborough and Ontario in 2006; i.e., what shape is each, and what does this tell you about the population of each of these areas? Use the names for pyramid shapes that are used in the Norton textbook.
(Note: the pyramids for Peterborough and Ontario are found in Ch. 8 of Peterborough and the Kawarthas.)
Location Description of population pyramids
Curve Lake
City of Peterborough Ontario
c. How do the population structures of Curve Lake, Peterborough and Ontario differ in 2006, if at all? If they differ, explain why this might be the case.
d. What does the shape of Ontario’s pyramid imply for future population growth in the province?
2. Dependency Ratios:
The dependency ratio (DR) is a measure of the portion of a population that falls outside of the productive cohort, which is generally designated as those people aged 15 to 64. Those who are 14 or younger, or over 65, are considered to be economically dependent on the remainder of the population. There are actually three dependency ratio.