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Fig. 1 | BMC Medical Research Methodology

Fig. 1

From: Alternative adjustment for seasonality and long-term time-trend in time-series analysis for long-term environmental exposures and disease counts

Fig. 1

Seasonality and time-trend in daily time-series in Seoul, 2002–2013. a PM10 concentration (μg/m3). b all-cause mortality (number of deaths/day), estimated by different functions of variables representing time. Abbreviation: df, degrees of freedom; doy, day of the week; NCS, natural cubic spline; I(year), an indicator function of year throughout the study period; NCS(doy,10df), NCS of day of the year with 10df; NCS(month,5df), NCS of the order of month throughout the study period with 5df; NCS(t,pdf/year), NCS of time throughout the study period with pdf per year; NCS(week,5df), NCS of the order of week throughout the study period with 5df; PM10, particulate matter with aerodynamic diameter ≤10 μm

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BMC Medical Research Methodology

ISSN: 1471-2288

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