• Proceedings of the Korean Statistical Society Conference
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• 2002.11a
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• pp.265-272
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• 2002

An Integer-valued autoregressive integrated (INARI) model is introduced to eliminate stochastic trend and seasonality from time series of count data. This INARI extends the previous integer-valued ARMA model. We show that it is stationary and ergodic to establish asymptotic normality for conditional least squares estimator. Optimal estimating equations are used to reflect categorical and serial correlations arising from panel count data and variations arising from three random processes for obtaining observation into estimation. Under regularity conditions for martingale sequence, we show asymptotic normality for estimators from the estimating equations. Using cancer mortality data provided by the U.S. National Center for Health Statistics (NCHS), we apply our results to estimate the probability of cells classified by 4 causes of death and 6 age groups and to forecast death count of each cell. We also investigate impact of three random processes on estimation.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.505-510
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• 2001

To improve germinability of carrot seeds of 'Inari', 'Mansan', 'Mussang', and 'Hongsim' cultivars, various levels of solid matrix priming (SMP) and the physiological changes of seeds associated with SMP were examined. As the ratio of water in a seed-Micro Cel E-water mix and priming duration increased, seed germinability enhanced. However, there was radicle protrusion during SMP in some cultivars, indicating the existence of cultivar different variations of the optimum conditions. The optimum ratio for a seed-Micro Cel E-water mix was 5 : 3 : 10.5. In this mix, the optimum durations for the treatment were 3 days for 'Mansan' and 5 days for other cultivars. SMP at $20^{\circ}C$ to $25^{\circ}C$ resulted in a higher germination percentage and a shorter $T_{50}$. Seeds absorbed water quickly within an hour and the percentage of moisture was stable at 43 to 49 after 24 hours of the treatment. Conductivity of the mix declined for the first 6 hours to $100{\mu}S{\cdot}cm^{-1}$ with little changes thereafter. On the other hand, the pH of the mixed increased slightly during the early phase, and then returned to the initial level as the treatment proceeded.