- Research your local area to find a cemetery that you may visit for this exercise.
Note: If you are unable to access a cemetery, you may use the data provided in the “HOL Supplied Cemetery Data” Supplemental Document. If you choose to do this, skip to step 9.
- Print a copy of Data Table 2, to bring with you to the cemetery. Travel to a cemetery during the day, ensure that conditions are safe and public access is permitted.
- In Data Table 2, record the name, birth date and date of death for 80 deceased individuals. As you collect data, be sure to spread out within the full sampling area. Individuals of the same family or who died in shared years will often be grouped together, and the goal is to take a representative sample of all individuals in the population.
- Record the cemetery name and location in Data Table 2.
- Determine how old each person was when they died, and record your data in Data Table 2. Use the following equation:
Age at death = Birth year – Death yearAge at death = Birth year – Death year
- Investigate the first names of each individual and record the sex (M for male; F for female) in Data Table 2. If the name is gender-neutral, such as Jean, Lynn, or Pat, you may leave the area blank. Ensure that any data you recorded by hand is present in the document that you report to your instructor. Photograph the sheet(s) of data you recorded. Upload the image into Photo 1.
Note: This concludes the outdoor portion of this exercise; the rest of Exercise 2 may be performed from home.
- Record a summary of the population. Address each of the following questions, and record data in Data Table 3.
- What were the first and last birth years?
- What were the first and last death years?
- How many individuals died before 1950? How many died after 1950?
- How many individuals are male and female?
- In the next steps, you will calculate the probability of dying within a given cohort. As shown in Data Table 4, cohorts are age classes. For example, cohort 1 includes individuals that died between the ages of 1 and 9; cohort 2 includes individuals who died between the ages of 10 and 19. Examine Data Table 4 and study the following descriptions for each column heading:
- Cohort (X) – The age intervals of deceased individuals.
- Number of Deaths (D) – The number of individuals that died in each cohort.
- Frequency of Population in Cohort (d) – The portion of the population that died in each cohort.
- Frequency of Survivorship Entering the Cohort (l) – The portion of the population that enters the cohort.
- Probability of Death within a Cohort (Q) – The probability that any given individual will die within a cohort.
- Count the number of people who died in each cohort (age interval). Record your data under “Number of deaths (D)” in Data Table 4.
- Calculate the “Frequency of population in cohort (d).” Record each value as a number with two decimal places. Use the following equation:
d = D / Total Population Sized = D / Total Population Size
Note: “Frequency of survivorship of cohort (l)” is based on entry into the cohort. Thus, the first cohort listed will always have a value of 1.00 because 100% of the population was born, entering into the cohort. A value of 1.00 has been entered for cohort # 1 in Data Table 4. With each subsequent cohort, values of “l” will decrease.
- Calculate the “Frequency of survivorship of cohort (l)” for cohort # 2. Record each value as a number with 2 decimal places. Use the following equation:
Icohort2 = Icohort1 – dcohort1Icohort2 = Icohort1 – dcohort1
- Calculate the “Frequency of survivorship of cohort (l)” for each of the remaining cohorts. For example, “Frequency of survivorship of cohort (l)” for cohort 3 will be calculated as:
Icohort3 = Icohort2 – dcohort2Icohort3 = Icohort2 – dcohort2
Note: The final recorded “l” in Data Table 4 should be equivalent or very close to the final recorded “d.”
- Calculate the “Probability of death (Q).” Record each value as a number with 2 decimal places.Use the following equation:
Q = d/IQ = d/I
Note: The probability of death is a frequency and may be interpreted as a percentage. For example, if Q = 0.30 for cohort # 1, then there is a 30% probability that a given individual will die between the ages of 1 to 9.
Note: To find Q, use data within a single cohort: Qcohort1 = dcohort1 / lcohort1
- Create a bar graph of the probability of death within each cohort. Plot the cohort age interval (1-9, 10-19, etc.) on the independent axis (x-axis), and plot the probability of death on the dependent axis (y-axis).
- Upload an image of the graph into Graph 3.