Page 276 - Contributed Paper Session (CPS) - Volume 2

CPS1855 Nobutane H.
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1985-1989 2010-2014 50-54 75-79

Figure 1. Age-specific breast cancer Figure 2. Trend in breast cancer
death rates in 1985-89 and that in 2010- death rates for 75-79 and that for
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2. Methodology
Our data to be analyzed in this study is given by age and period as
indicated in Table 1. The Lexis diagram (Keiding, 1990) indicated in Figure 3 is
useful tool for understanding the properties of this type of data. In the figure
the vertical axis indicates age and the horizontal axis indicates time (year). And
those oblique lines indicate individuals who are alive and they die at the
endpoints of those oblique lines.

Figure 3. Lexis diagram Figure 4. Death rates on the Lexis
diagram

On the Lexis diagram the number of deaths given by 5-year age and
period, say ; = 1,2, … , ; = 1,2, … , , equals the number of end points of

those oblique lines within the squared area [ −1 , ) × [ −1 , ), where

−1 , = −1 , = 5, and death rate given by age and period, that is given

for [ −1 , ) × [ −1 , ) say  , equals the expectation of divided by the

total of individuals’ survival time with in [ −1 , ) × [ −1 , ) say . Because

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