Lab #4 Human Ecology
NAME________________________________________
**These instructions below are for people who use the 2007 version of Microsoft.
Instructions
Under “Resources”, download and read the “ ” file (http://esa21.kennesaw.edu/activities/populationage/populationage ) before completing this answer sheet for Lab #4. The ‘pdf’ is the lab. This MS Word ‘ ’ is the answer sheet. You are to fill in the answer sheet and submit it for grading. Once you have completed the answers for the lab, save your document on your computer as “JohnDoeLab4” (or something similar). You’ll be attaching this document in the assignment for me to grade. To attach your answer sheet for Lab #4, go to “Assignments” section of class. Click Lab #4 and upload your answer sheet. Then check ‘submit for grading’ and click ‘ok’ so I know it’s ready!
Activity
Gathering Population Data
On Page 3 of the lab ( ), you are given the following background and instructions to find population data for each age group and sex from the 2000 census for the American Indian and Alaska Native group. Because emigration and immigration are not major factors influencing the population numbers for this group, one can see the future of the group’s population without substantial migration influences. Here is an excerpt from the lab ( ):
Click on the following link to gather data for the number of
females
in each age group for the American Indian and Alaska Native. Be sure you use the column specified for that group:
http://www.census.gov/population/cen2000/phc-t9/tab03
Click on the following link to gather data for the number of
males
in each age group for the American Indian and Alaskan Native. Be sure you use the column specified for that group:
http://www.census.gov/population/cen2000/phc-t9/tab02
Using the datasheets from these links, complete the following. You will be using MS Excel to produce a diagram or graph (rather than drawing one as the pdf instructs). Once you are finished constructing the graph, you are to insert/paste it on page 3 of this document below.
All of page 3 will be graded, including the graph and remaining 2 questions at the end.
Lab instructions
– Constructing and Graphing an Age Structure Diagram
In this section you will use your data from the links above to create an age structure graph. An example of an age structure – or population pyramid – can be seen on page 153 of your textbook.
What is the shape of your population’s age structure? Use the following methods to create a graph of the age structure of your population. Follow the instructions below, step-by-step.
1. Open a spreadsheet in Excel.
2. Highlight column A, select Format Cells, Text.
3. Type in your data into the spreadsheet in the following format (see example below). It may be best to have a friend/family member read the data from the data links while you type.
a. Type “
Age Class
” in cell A1 and type the age categories (i.e.
0-4
,
5-9
, 10
–
14
, etc.) down this first column.
b. Type “
Female
” in B1 and then type the female values into this second column.
c. Type “
Male
” in C1 and then type the male values into this third column. INCLUDE A NEGATIVE SIGN BEFORE EACH # IN THE MALE COLUMN. (i.e. -20, -14, etc).
d. Proof your data. Read the values again while you check them on the screen.
Example of data entry:
Age Class | Female | Male |
0-4 |
10 (or whatever your data is) |
– 12 |
5-9 | 12 | -14 |
10-14 |
14 |
-16 |
Etc. |
4. Highlight your data (click and drag all the cells you’ve entered text or data for) including the column titles. Either right click or go up the menu on the top bar and select ‘Insert’, ‘Bar Chart’.
5. Select “2D”, ‘Clustered Bar Chart’ subtype. (Notice there are different sub-types – the name of the type appears as you hover above the examples. Choose ‘clustered bar’).
6. Click Layout (under Chart tools on top bar), and then Chart Title on the sub bar.
a. In Chart Title, select ‘Above Chart’ and type “Age Structure of American Indian and Alaska Native”.
b. Go back to Layout and click Axis Titles (next to Chart Title). Select Vertical, Rotated Title. Type “Age Class” (4-year intervals).
c. Go back to Layout and click Axis Titles (next to Chart Title). Select Horizontal, Title Below Axis. Type “Male, Female” (thousands).
d. Select the Gridlines tab and deselect all gridlines.
e. Select the Legend tab and select Bottom placement of the legend.
7. Hold the cursor over one of the bars in the graph until it indicates Series and then double click the mouse.
8. Select Format Selection (far left) and Series Overlap. Type in 100. Under Gap Width, Type in 0. Click OK.
9. Hold the cursor in the graph beyond the bars until it indicates Plot Area. Select None.
10. Click once to the left of the title of your graph to highlight the entire graph. Go to the Edit menu, click “cut”. Then “paste” right here and save the MS Word document!
Results
INSERT GRAPH HERE!
Questions
1. Take a look at the shape of the diagram you have constructed. Would you say the diagram reveals a rapidly growing population, a numerically stable population, or a population facing negative growth? Explain how you made your decision.
2. Using the three age structure diagram examples from Mexico, Japan, and Iceland that you observed in the lecture portion of this activity, which one of these 3 countries is most comparable to the age structure diagram you constructed for the American Indian and Alaska Native?
Population: Age Structure
One of the tools that demographers use to understand population is the age structure diagram (it is
sometimes called a population pyramid, but it is not always pyramidal in shape).
This diagram shows the
distribution by ages of females and
males within a certain population in
graphic form. Figure 1 shows a
diagram in which the ages and sexes for
the United States population are
arranged so that ages are grouped
together such as 0 – 4 years, 5 – 9
years, and so on. The population of
each is group is represented as a bar
extending from a central vertical line,
with the length of each bar dependent
upon the population total for that
particular group. The centerline
separates the females from the males.
The female and male populations for
each group are represented by the
distance from the centerline, with
females on the right and males on the
left.
Fig. 1: Age Structure diagram for the U.S.
Age and Sex Distribution
By looking closely at the age structure diagram, one will notice slightly more boys in the younger age
groups than girls; however, the ratio tends to reverse in the upper age groups, as females tend to
outnumber males. Many countries have a female majority as a result of the longer life expectancy for
females. In the United States, this ratio change is clearly shown in the table below showing age and sex
distribution in the census year 2000. Notice that at about age 35, the majority changes.
Number
Age Both sexes Male Female
Total population 281,421,906 138,053,563 143,368,343
Under 18 years 72,293,812 37,059,196 35,234,616
18 to 64 years 174,136,341 86,584,742 87,551,599
18 to 24 years 27,143,454 13,873,829 13,269,625
25 to 44 years 85,040,251 42,568,327 42,471,924
45 to 64 years 61,952,636 30,142,586 31,810,050
65 years and over 34,991,753 14,409,625 20,582,128
Median age (years) 35.3 34.0 36.5
In China, the age and
sex distribution is
cause for alarm.
Efforts there to
reduce the birth rate
have apparently
contributed to a
prominent male
majority. Since the
early 1980’s, a thrust
by the government to
reduce population
growth in the most
populous country in
the world has resulted
in many parents
actively trying to have
a male child if they
are to have only one child. Cultural traditions there tend to cause parents to see a male child as more
beneficial to the family than a female child; therefore, a striking imbalance has resulted between the
numbers of males and females. There are concerns that the imbalance could lead to instabilities.
Fig. 2: Age structure diagram for China
Constructing and Interpreting an Age Structure Diagram
With age and sex distribution data from a certain
population, it is easy to construct an age structure
diagram. Once the diagram is constructed, one can
clearly see if the population will grow, decline, or
experience no noticeable change in its population
numbers; for example, if the diagram shows a
pyramidal shape, then one can expect a rapid rise in
population. If the diagram shows a generally straight
up and down shape except for the older age groups, a
stable population is thus revealed. If the diagram
shows a top-heavy shape, then a decline is forecast
for that population.
Figure 3 shows the age structure diagrams for Mexico,
Iceland, and Japan. The different shapes seen in the
diagrams reflect different population characteristics.
The diagram for Mexico shows the unmistakable
pyramidal shape caused by ever-increasing number of
births. Japan’s diagram has the classic shape of a
shrinking population. In it, you should note how pre-
reproductive age groups (0 – 14 years) have smaller
populations than the reproductive age groups (15 – 44
years). Iceland shows a more stable population.
Except for the post-reproductive groups (45+ years),
the populations for the age groups extend generally
the same lengths.
Fig. 3: Age structure diagrams for Mexico,
Iceland, and Japan (U.S. Census Bureau)
Activity: Constructing an Age Structure Diagram
On the activity sheet is an age structure diagram template on which bars can be drawn to represent the
population for each age group and sex. Data for constructing the diagram will come from Census Year
2000 data for the American Indian and Alaska Native group. Because emigration and immigration are not
major factors influencing the population numbers for this group, one can see the future of the group’s
population without substantial migration influences.
Click on the following link to gather data for the number of females in each age group for the American
Indian and Alaska Native. Be sure you use the column specified for that group:
http://www.census.gov/population/cen2000/phc-t9/tab03
Click on the following link to gather data for the number of males in each age group for the American
Indian and Alaskan Native. Be sure you use the column specified for that group:
http://www.census.gov/population/cen2000/phc-t9/tab02
Using the datasheets linked above, draw bars on the age structure diagram template to represent the
populations for each age group of males and females. Three bars have already been drawn to
demonstrate how it is to be done. The task can be done with a pencil and straight edge. Be sure to add
color to the bars for added clarity and appeal.
Once finished with constructing the diagram, answer the questions on the activity sheet.
http://www.census.gov/population/cen2000/phc-t9/tab03
http://www.census.gov/population/cen2000/phc-t9/tab02
Activity Sheet Age Structure
Name:
1. Take a look at the shape of the diagram you have constructed. Would you say the diagram reveals a
rapidly growing population, a numerically stable population, or a population facing negative growth?
Explain how you made your decision.
2. Using the three age structure diagram examples from Mexico, Japan, and Iceland that you observed
in the lecture portion of this activity, which one of these 3 countries is most comparable to the age
structure diagram you constructed for the American Indian and Alaska Native?
- Introduction
Age and Sex Distribution
Constructing and Interpreting an Age Structure Diagram
ESA21: Environmental Science Activities