en عمومى General پژوهشي Research <span style="font-size:12pt"><span new="" roman="" style="font-family:" times=""><span lang="EN-US" style="font-size:11.0pt">Modeling the temporal dynamics of COVID-19 is important for understanding the progression of the pandemic. This study fitted Autoregressive Integrated Moving Average (ARIMA) models to the daily numbers of confirmed COVID-19 cases and deaths in seven countries: the USA, Spain, the UK, Italy, Iran, Germany, and France. The dataset covered the period from February to April 2020. Model structures were identified using the autocorrelation function (ACF) and partial autocorrelation function (PACF), and the final models were selected based on the corrected Akaike Information Criterion (AICC) and Bayesian Information Criterion (BIC). Model adequacy was evaluated using residual diagnostics, including ACF/PACF plots and the Ljung&ndash;Box test, which showed no significant residual autocorrelation for the selected models. The results indicate that ARIMA models provide an adequate statistical framework for describing the temporal dependence structure of daily COVID-19 time series and offer a basis for further short-term analyses.</span></span></span><br> &nbsp; COVID-19, Autoregressive Integrated Moving Average (ARIMA), Time Series Analysis. 11 23 http://ijorlu.lahijan.iau.ir/browse.php?a_code=A-10-629-1&slc_lang=en&sid=1 M. Maroufi maroufi172@gmail.com 10031947532846002546 10031947532846002546 No Department of Statistics, Marv.C., Islamic Azad University, Marvdasht, Iran K. Zare karim.zare@iau.ac.ir 10031947532846002547 10031947532846002547 Yes Department of Statistics, Marv.C., Islamic Azad University, Marvdasht, Iran M. R. Mahmoudi mahmoudi.m.r@fasau.ac.ir 10031947532846002548 10031947532846002548 No Department of Statistics, Faculty of Science, Fasa University, Fasa, Iran D. Jamali dariush.jamali@iau.ac.ir 10031947532846002549 10031947532846002549 No Department of Statistics, Marv.C., Islamic Azad University, Marvdasht, Iran Z. Sajjadian zahra.sj1999@gmail.com 10031947532846002550 10031947532846002550 No Bank Pasargad, Shiraz, Iran