# Our Team

The Data and Decision Sciences Lab is composed of top-tier researchers with years of experience in data science, operations research, and statistics projects.

## Steven G. From, Ph.D.

### Professor

Ph.D., Mathematical Statistics, University of Nebraska–Lincoln, 1985

B.S., Mathematics, Creighton University, 1979

#### Contact Information

#### Location

Department of Mathematics

Durham Science Center

6001 Dodge Street, Omaha, NE 68182

Office: DSC 236

#### Research Interests

### Academic and Professional Experience

Steven joined the department of Mathematics at the University of Nebraska at Omaha in 1986 as an Assistant Professor. He received a Ph.D. in Mathematical Statistics from the department of Mathematics and Statistics at the University of Nebraska–Lincoln in 1985. He also taught operations research for one semester as a Visiting Assistant Professor at the University of Nebraska–Lincoln in the department of Mathematics and Statistics during 1986. Steven has taught over 25 different courses in both mathematics and statistics in his 34 year career. He has also given numerous independent studies in statistics, probability, and analysis.

Steven has published research papers in mathematical statistics, applied statistics, applied probability theory, reliability theory, mathematical inequalities in probability, statistics and analysis, differential equations, computer science applications, and has collaborated with many individuals outside the department including researchers at the University of New Orleans, Rutgers University, Creighton University, and Victoria University in Australia. Recently, his research has focused more on mathematical inequalities, including some which have applications in probability and statistics, such as Jensen’s inequality.

Steven has won several awards, including the Kerrigan Teaching award as well as the James Earl Diamond Professorship of Mathematics in 2006. During his Kerrigan research grant, his students have done well, including one first place finish and one second place finish in a student mathematics research competition. Prior to 2005, Steven was one of only two faculty trained in statistics as their primary research area, and he did significant statistical consulting with other faculty and students, including faculty and students from the University of Nebraska Medical Center and Creighton University. He has done statistical consulting work with individuals outside the university, including local area educators and Engineers as well. He also has supervised the Master’s thesis of eight students, three of which went on to obtain a Ph.D. in mathematics, statistics or some other related area. He lists this as one of his greatest accomplishments.

### Selected Publications

Dragomir S., and **From S.**, Some Inequalities for an Integrable Operator and
*n*-time Differentiable Functions, *Acta Mathematica Universitatis Comenianae, 89*
(2), 195-213 (2020).

**From S.**, Some New Upper and Lower Bounds for the Mills Ratio,
*Journal of Mathematical Analysis and Applications*, 486(1), 123782, 25 pp. (2020).

**From S.**, and Swift A. W., Some New Bounds and Approximations on Tail Probabilities of the Poisson and Other Discrete Distributions,
*Probability in the Engineering and Informational Sciences*, 34(1), 53-71 (2020).

**From S.**, and Dragomir S., Some New Refinements of Jensen’s Discrete Inequality,
*Sarajevo Journal of Mathematics*, 15(28) 37-48 (2019).

**From S.**, Some New Inequalities of Hermite-Hadamard and Fejer Type for Certain Functions with Higher Convexity,
*Australian Journal of Mathematical Analysis and Applications*, 14(1), Article 10, 17 pp. (2017).

**From S.**, Nonparametric Confidence Intervals for the Extinction Probability in a Galton-Watson Branching Process,
*Communications in Statistics – Theory and Methods*, 46(3), 1202-1217 (2017).

**From S.**, Some New Generalizations of Jensen’s Inequality with Related Results and Applications,
*Australian Journal of Mathematical Analysis and Applications*, 13(1), Article 1, 29 pp. (2016).

Bonham-Carter O., Thapa I., **From S.**
, and Bastola D., A Study of Bias and Increasing Organismal Complexity from their Post-Translational Modifications and Reaction Site Interplays, *Briefings in Bioinformatics*
, 18(1), 69-84 (2016).

**From S.**, Some New Inequalities for a Sum of Exponential Functions,
*Applied Mathematical Sciences*, 9(109), 5429-5439 (2015).

**From S.**, and Swift A. W., A Refinement of Hoeffding’s Inequality,
*Journal of Statistical Computation and Simulation*, 83(5), 975-981 (2013).

**From S.**, A Comparison of the Moment and Factorial Moment Bound for Discrete Random Variables,
*The American Statistician*, 66(4), 214-216 (2012).

**From S.**, An Improved Hoeffding’s Inequality of Closed Form Using Refinements of the Arithmetic Mean-Geometric Mean Inequality,
*Communications in Statistics – Theory and Methods*, advance online publication (2013).

**From S.**, Heidel J., and Maloney J., On the Location and Nature of Derivative Blowups of Solutions of Certain Nonlinear Differential Equations,
*Far East Journal of Mathematical Sciences*, 50(1), 22 pp. (2011).

**From S.**, Some New Reliability Bounds for Sums of NBUE Random Variables,
*Probability in the Engineering and Informational Sciences*, 25(1), 83-102 (2011).

**From S.**, and Swift A. W., Generalized Median Estimators for Small Even Sample Sizes,
*Advances and Applications in Statistical Sciences*, 4(2), 145-164 (2010).

**From S.**, and Swift A. W., Convolution of Independent Bernoulli Random Variables and Some New Approximations,
*Advances and Applications in Statistical Sciences*, 2(1), 37-50 (2010).

**From S.**, and Maloney J., Approximation of Poles and Branch Points of Solutions of Solutions to Certain Nonlinear Differential Equations Using Modified Piecewise Pade Approximations,
*Journal of Algorithms and Computational Technology*, 4(1), 15-25 (2010).

**From S.**, Some Bounds on the Deviation Probability for Sums of Nonnegative Random Variables Using Upper Polynomials, Moment and Probability Generating Functions,
*Missouri Journal of Mathematical Sciences*, 22(1), 23-36 (2010).

**From S.**, Distance between Vertical Asymptotes of Solutions of Certain Nonlinear Differential Equations,
*Computers and Mathematics with Applications*, 55(11), 2444-2451 (2008).

**From S.**, Some New Bounds on the Probability of Extinction of a Galton-Watson Process with Numerical Comparisons,
*Communications in Statistics – Theory and Methods*, 36(10), 1993-2009 (2007).

**From S.**, and Li L., Estimation of the Parameters of the Birnbaum-Saunders Distribution,
*Communications in Statistics – Theory and Methods*, 35 (12), 2157-2169 (2006).

**From S.**, Prediction Intervals for a Renewal Counting Process,
*Journal of Statistical Theory and Applications*, 5(1), 71-80 (2006).

**From S.**, Lower Bounds and Approximations of the Locations of Movable Singularities of Some Nonlinear Differential Equations Using Parametrized Bounded Operators,
*Applied Mathematics and Computation*, 175(1), 16-37 (2006).

**From S.**, Bounds for Asymptote Singularities of Certain Nonlinear Differential Equations,
*Journal of Inequalities in Pure and Applied Mathematics*, 7(1), 36 pp. (2006).

**From S.**, and Tortorella M.,
Parametric Confidence Intervals for the Renewal Function Using Coupled Integral Equations, *Communications in Statistics – Simulation and Computation*
, 34(3), 663-672 (2005).

**From S.**, and Li L., Nonparametric Confidence Intervals for the Renewal Function,
*Journal of Applied Statistical Science*, 13 (3), 203-215 (2004).

**From S.**, Approximating the Distribution of a Renewal Counting Process Using a Family of GPD Distributions,
*Journal of Statistical Computation and Simulation*, 74 (9), 667-681 (2004).

**From S.**, Confidence Intervals for Gini’s Diversity Measure and Shannon’s Entropy Using Adjusted Proportions,
*Communications in Statistics – Theory and Methods*, 35(5), 935-954 (2003).

**From S.**, and Li L., Nonparametric Estimation of some Quantities of Interest from Renewal Theory,
*Naval Research Logistics*, 50(6), 638-649 (2003).

**From S.**, Some New Approximations for the Renewal Function,
*Communications in Statistics – Simulation and Computation*, 30(1), 115-130 (2001).

Memon M., Devine J., Freeney J., and **From S.**
, Is Mechanical Bowel Preparation Really Necessary for Left Sided Colon and Rectal Surgery, *International Journal of Colorectal Diseases*
, 12(5), 298-302 (1997).

Juhler S., Rech J., **From S.**
, and Brogan M., The Effect of Optional Retesting on College Students’ Achievement in an Individualized Algebra Course, *The Journal of Experimental Education*
, 66(2), 125-137 (1998).

**From S.**, A New Goodness of Fit Test for the Equality of Multinomial Cell Probabilities Versus Trend Alternatives,
*Communications in Statistics – Theory and Methods*, 25(12), 3167-3183 (1996).

**From S.**, A Two-Stage Procedure for Estimating the Parameters of Some Discrete Distributions,
*Journal of Statistical Computation and Simulation*, 53(1-2), 23-39 (1995).

**From S.**, A Weighted Least Squares Procedure for Estimating the Parameters of Altham’s Multiplicative Generalization of the Binomial Distribution,
*Statistics and Probability Letters*, 25(3), 193-199 (1995).

Farhat H., and **From S.**,
A Quadratic Programming Approach to Estimating the Testability and Random or Deterministic Coverage of a VLSI Circuit, *VLSI Design*
, 2(3), 223-231 (1994).

**From S.**, Some Recurrence Relation Based Estimators of the Parameters of a Generalized Log-Series Distribution,
*Communications in Statistics – Theory and Methods*, 22(6), 1653-1664 (1993).

Farhat H., and **From S.**,
A Beta Model for Estimating the Testability and Coverage Distributions of a VLSI Circuit, *IEEE Transactions on Computer-Aided Design of Integrated Circuits and Systems*
, 12(4), 550-554 (1993).

Farhat H., and **From S.**,
Bounds on Population Coverage Using Test Generation by Fault Sampling, *Microprocessors and Microsystems*, 16(5), 269-275 (1992).

**From S.**, and Farhat H., Confidence Intervals for Expected Coverage from a Beta Testability Model,
*Computers and Mathematics with Applications*, 24(7), 97-107 (1992).

**From S.**, Mean Square Error Efficient Estimation of an Exponential Mean Under an Exchangeable Single Outlier Model,
*Communications in Statistics – Simulation and Computation*, 20(4), 1073-1084 (1991).

**From S.**, Estimating Means from a Non-IID Mixture of Poisson Samples,
*Annals of the Institute of Statistical Mathematics*, 43(1), 167-179 (1991).

**From S.**, Nonparametric Estimation of a Changepoint in Positive Shift Models,
*Communications in Statistics – Theory and Methods*, 19(9), 3163-3173 (1990).

**From S.**, An Application of Cheng’s Lemma for Minimizing the Asymptotic Variance of Best Asymptotically Normal Estimators Based on Sample Quantiles, Journal
*of Statistical Planning and Inference*, 26(3), 363-370 (1990).

**From S.**, On the Performances of Some Selection Procedures for the Best Population Assuming Parent Distributions with Varying Tailweight,
*Journal of Statistical Computation and Simulation*, 33(1), 27-35 (1989).

**From S.**, Optimal Spacing of Quantiles for the Estimation of the Mixing Parameters in a Mixture of Two Exponential Distributions,
*Communications in Statistics – Theory and Methods*, 18(6), 2201-2223 (1989).

**From S.**, Lal Saxena K., Estimating Parameters from Mixed Samples Using Sample Fractional Moments,
*Journal of Statistical Planning and Inference*, 21(2), 231-244 (1989).

### Current Students Advised

#### Yao Todo

Graduate Student

**Research: **Estimating Parameters of Distributions Using Mean Residual Life Functions

### Past Students Advised

#### Godfred Amoah

Graduate Student

**Research: **Approximating the Distribution of the Sum of Independent and Dependent Bernoulli Random Variables with an Application to the Two State Markov Chain
**
Year: **2016

#### Naif Alghamdi

Graduate Student

**Research: **Confidence Intervals for Ratios of Multinomial Proportions
**
Year: **2015

#### Suthakaran Ratnasingam

Graduate Student

**Research: **Statistical Modelling for Extreme Precipitation in Sri Lanka
**
Year: **2015

#### Tyler Brown

Graduate Student

**Research: **Some New Closed-Form Small-Sample Estimators for the Linear Failure Rate and Birnbaum-Saunders Distributions
**
Year: **2015

#### Nirosha Rathnayake

Graduate Student

**Research: **Approximation of Expected Values of Non-Linear Functions of Random Variables
**
Year: **2012

#### Rodney Tembo

Graduate Student

**Research: **Asymptotic Confidence Intervals for Certain Functions of Population Moments
**
Year: **2012

#### Beichen Wang

Graduate Student

**Research: **Approximating Discrete Distributions Using Rational Functions
**
Year: **2011

#### Bingyong Deng

Graduate Student

**Research: **Approximations and Bounds for the Extinction Probability of a Galton-Watson Branching Process
**
Year: **2011