Publications

· Djira, G.D. Relative potency estimation in parallel-line assays – Method comparison and some extensions (Accepted).

· Djira, G.D., Schaarschmidt, F. and Fayissa, B. Inferences for selected location quotients with applications to health outcomes. Geographical Analysis (Accepted).

· Djira, G.D. and Hothorn, L.A. (2009). Detecting relative changes in multiple comparisons with an overall mean. Journal of Quality Technology 41, 60 - 65.

· Djira, G.D., Hothorn, L.A., and Tsong, Y. (2008). Equivalence tests for shelf life and average drug content in stability studies. Journal of Biopharmaceutical Statistics 18, 985 - 995.

· Djira, G.D., Guiard, V., and Bretz, F. (2008). Efficient and easy-to-use sample size formulas in ratio-based non-inferiority tests. Journal of Applied Statistics 35, 893 - 900.

· Dilba, G., Schaarschmidt, F., Hothorn, L.A. (2007). Inferences for ratios of normal means. RNews 7(1):20-23.

· Dilba, G. and Schaarschmidt, F (2007). R extension software package, mratios: A package for simultaneous inferences for ratios of coefficients in the general lineal model.

· Dilba, G., Bretz, F., Hothorn, L.A., Guiard, V. (2006). Power and sample size computations in simultaneous tests for non-inferiority based on relative margins. Statistics in Medicine 25, 1131-1147.

· Dilba, G., Bretz, F., Guiard, V. (2006). Simultaneous confidence sets and confidence intervals for multiple ratios. Journal of Statistical Planning and Inference 136, 2640-2658.

· Dilba, G., Aerts, M. (2004). A comparative study of models for correlated binary data with applications to health services research. SINET: Ethiopian Journal of Science 27, 97-104.

· Dilba, G., Bretz, F., Guiard, V. and Hothorn, L.A. (2004). Simultaneous confidence intervals for ratios with applications to the comparison of several treatments with a control. Methods of Information in Medicine 43, 465-469.

· Dilba, G. (1995). A study on error sizes in sequential probability ratio test. Journal of the Ethiopian Statistical Association 4, 1-7.

Talks

o Inferences for ratios of regression parameters using Bayesian approach. Computational Science and Statistics seminar, Oct 22, 2099 (with Frank Schaarschmidt)

o Multiple comparisons for mean response profiles in longitudinal studies. Joint Statistical Meeting, Washington DC, Aug 2009 (Poster presentation with Ramu Sudhagoni)

o Simultaneous confidence bands for multi-dimensional effective doses, 15^th Anniversary of the Institute of Biostatistics, Hannover, Germany, Dec 12, 2008.

o Simultaneous confidence bands for multi-dimensional effective doses in chemical mixture models, Joint Statistical Meeting, Denver, Aug 3-7, 2008 (with Din Chen).

o Relative potency estimations in multiple parallel-line assays. Seminar: University Center, Sioux Falls, Oct 11, 2007.

o Relative potency estimations in multiple bioassay problems. 5^th International Conference on Multiple Comparison Procedures, Vienna, July 8-11, 2007.

o Multiplicity adjusted location quotients. 5^th International Conference on Multiple Comparison Procedures, Vienna, July 8-11, 2007 (Poster presentation with Frank Schaarschmidt and Bichaka Fayissa).

o Alternative methods of pooling batches in drug stability studies. First joint statistical meeting - Statistics under one umbrella, Bielefeld, Germany, March 2007 (with Hothorn).

o Tests for relative changes in multiple comparisons with an overall mean. Hannover Biometric Colloquium, January 2007 (with Hothorn, L.A)

o Inferences for relative degradation rates of batches in drug stability studies. International conference on non-clinical statistics, Potsdam, Germany, Sep 2006 (with Hothorn, L.A.)

o Simultaneous inferences for ratios of coefficients in the general linear model. 23^rd International Biometric Conference, Montreal, July 2006 (with Hothorn, L.A.)

o mratios: An R package for inferences about ratios of normal means. UseR Conference, June 2006, Vienna (with Schaarschmidt, F. and Hothorn, L.A.)

o Simultaneous confidence intervals for ratios of means using Bayesian approach. March 2006, Bochum (with Bretz, F. and Hothorn, L.A.)

o On the relative efficiency of ratio-formatted hypotheses in multple tests, Basel, Switzerland, October 2005 (with Bretz, F., Hothorn, L.A. and Guiard, V.).

o Power and sample size computations in simultaneous tests for non-inferiority based on relative margins, Martin-Luther-Universitdt, Halle-Wittenberg, March 2005 (with Bretz, F., Hothorn, L.A. and Guiard, V.).