1. Human Life Tables and Survivorship Curves

2. Test hypotheses about human survivorship using:
PURPOSE:
Test hypotheses about human survivorship using:
Life tables
life expectancy
Survivorship curves

3. Hypotheses about Males and Females
H1 Females have a greater life expectancy than males because of risky male behaviors and the toxic effects of testosterone.
prediction: the survivorship curve and the calculated life expectancy for females is higher than that for males.
H2 Females are more likely to die during the reproductive years because of the risks associated with pregnancy.
prediction: the calculated life expectancy for males during the reproductive years is higher than that for females and the dx value is greater for females during the reproductive years.

4. Hypotheses about Public Health
H3 Human life expectancy has increased with time due to advances in medicine, nutrition, and sanitation.
prediction: survivorship curves and calculated life expectancies are higher for newer graveyards.
BRB
R.I.P.

5. What are life tables?
A life table contains age-specific survival and mortality rates in a population. It also contains fecundity and age distribution information.
Life tables come in 2 varieties:
Cohort life table: Follows a group of individuals born at the same time.
Static life table: Constructed by recording the age at death of a large number of individuals. This is what we’ll be making.

6. Example Life Table x Dx Nx lx ax qx 1000lx log1000lx 0-5 1 4.00 250.00
1.00
0.98
0.02
3.00
6-10 2
0.00
246.00
984.00
2.99
11-15 3
16-20 4
245.00
0.99
0.01
980.00
21-25 5
242.00
0.97
968.00
26-30 6
239.00
0.96
956.00
2.98
31-35 7
36-40 8
2.00
236.00
0.94
944.00
2.97
41-45 9
234.00
936.00
46-50 10
12.00
233.00
0.93
0.95
0.05
932.00

7. X = a reference number we assigned to refer to the different classes
Life Tables
Age Class x dx nx lx ax
0-5 1
6-10 2
11-15 3
Etc.
X = a reference number we assigned to refer to the different classes

8. X = a reference number we assigned to refer to the different classes
Life Tables
Age Class x dx nx lx ax
0-5 1
x-1
6-10 2
11-15 3
Etc.
X = a reference number we assigned to refer to the different classes

9. X = a reference number we assigned to refer to the different classes
Life Tables
Age Class x dx nx lx ax
0-5 1
6-10 2
11-15 3
x+1
Etc.
X = a reference number we assigned to refer to the different classes

10. dx Life Tables Age Class x nx lx ax 0-5 1 6 6-10 2 11-15 3 Etc.
Etc.
dx= the number of individuals that die in the x age class.

11. nx Life Tables Age Class x dx lx ax 0-5 1 6 6-10 2 11-15 3 Etc.
How many?
6-10 2
11-15 3
Etc.
nx= total number of individuals surviving to the x age class.
nx0 (the first nx ) is always the sum of dx

12. nx Life Tables Age Class x dx lx ax 0-5 1 6 100 6-10 2 11-15 3 Etc.
How many?
11-15 3
Etc.
nx= total number of individuals surviving to the x age class.
nx = nx-1- dx-1

13. nx Life Tables Age Class x dx lx ax 0-5 1 6 100 6-10 2 94 11-15 3 Etc.
Etc.
nx= total number of individuals surviving to the x age class.
nx = nx-1- dx-1

14. nx Life Tables Age Class x dx lx ax 0-5 1 6 100 6-10 2 94 11-15 3 9292
Etc.
nx= total number of individuals surviving to the x age class.
nx = nx-1- dx-1

15. lx Life Tables Age Class x dx nx ax qx 0-5 1 6 100 6-10 2 94 lx =?
6-10 2 94
lx =
11-15 3 92
Etc.
(lx) Survivorship: Portion of population that survived to the x age class

16. lx Life Tables Age Class x dx nx ax qx 0-5 1 6 100 6-10 2 94 .94 lx =
11-15 3 92
Etc.
(lx) Survivorship: Portion of population that survived to the x age class

17. lx Life Tables Age Class x dx nx ax qx 0-5 1 6 100 6-10 2 94 .94 lx =
11-15 3 92
.92
Etc.
(lx) Survivorship: Portion of population that survived to the x age class

18. ax Life Tables Age Class x dx nx lx qx 0-5 1 6 100 6-10 2 94 .94 11-153 92
.92
ax =
Etc.
ax = Given you reach the x age class, what is the probability you live to the NEXT age class.

19. ax Life Tables Age Class x dx nx lx qx 0-5 1 6 100 6-10 2 94 .94 11-15
=94/100
6-10 2 94
.94
11-15 3 92
.92
ax =
Etc.
ax = Given you reach the x age class, what is the probability you live to the NEXT age class.

20. qx Life Tables Age Class x dx nx lx ax 0-5 1 6 100 .94 6-10 2 94 11-153 92
.92
Etc.
qx = Given you reach the x age class, what is the probability you do NOT live to the NEXT age class.

21. qx Life Tables Age Class x dx nx lx ax 0-5 1 6 100 .94 6-10 2 94 .98
11-15 3 92
.92
Etc.
qx = Given you reach the x age class, what is the probability you do NOT live to the NEXT age class.

22. qx Life Tables Age Class x dx nx lx ax 0-5 1 6 100 .94 6-10 2 94 .98
11-15 3 92
.92
qx =
Etc.
qx = Given you reach the x age class, what is the probability you do NOT live to the NEXT age class.

23. qx Life Tables ax + qx = 1 Age Class x dx nx lx ax 0-5 1 6 100 0.94
6-10 2 94
0.98
11-15 3 92
0.92
Etc.
ax + qx = 1

24. qx Life Tables ax + qx = 1 Age Class x dx nx lx ax 0-5 1 6 100 0.94
0.06
6-10 2 94
0.98
0.02
11-15 3 92
0.92
Etc.
ax + qx = 1
Make three: Males, Females, and Totals for your group’s data

25. Life Expectancy
How can we test whether health issues influence survivorship, or if there is a difference between males and females?
The amount of time one is expected to live once age class x is reached or during a specified period of time.

26. Use your lab sections’ data: Compute life expectancies for all age groups and for childbearing years. Do this for Males, Females, and Totals
Compute life expectancies for the older cemetery and the younger cemetery.
You will have 8 life ex values

27. Survivorship curves: Make 2: your data (Male vs. Female)
previous data (Old vs. New)
BRB
R.I.P.

29. Graph dx for males vs. females and old vs. new. What does this tell us?

30. Binomial tests
Male vs. female
Male vs. female childbearing

31. A lot of data… To leave today you need
1) Three life tables (male, female, all) using lab section’s data
2) Eight life expectancies
3) Survivorship curve (M and F) (lab section data)
4) Survivorship curve (Old and New) (Previous Data)
5) dx graphs
6) Binomial tests: male vs. female and male vs. female childbearing (all five lab sections)

32. Shoes for next week
No good
Good
Okay