Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-10T14:59:45.907Z Has data issue: false hasContentIssue false

Statistical Inference Involving Binomial and Negative Binomial Parameters

Published online by Cambridge University Press:  10 January 2013

Miguel A. García-Pérez*
Affiliation:
Universidad Complutense (Spain)
Vicente Núñez-Antón
Affiliation:
Universidad del País Vasco (Spain)
*
Corresponding Author's Address: Miguel A. García-Pérez, Departamento de Metodología, Facultad de Psicología, Universidad Complutense, Campus de Somosaguas, 28223 Madrid, Spain. Phone: +34 913 943 061; Fax: +34 913 943 189; E-mail: miguel@psi.ucm.es

Abstract

Statistical inference about two binomial parameters implies that they are both estimated by binomial sampling. There are occasions in which one aims at testing the equality of two binomial parameters before and after the occurrence of the first success along a sequence of Bernoulli trials. In these cases, the binomial parameter before the first success is estimated by negative binomial sampling whereas that after the first success is estimated by binomial sampling, and both estimates are related. This paper derives statistical tools to test two hypotheses, namely, that both binomial parameters equal some specified value and that both parameters are equal though unknown. Simulation studies are used to show that in small samples both tests are accurate in keeping the nominal Type-I error rates, and also to determine sample size requirements to detect large, medium, and small effects with adequate power. Additional simulations also show that the tests are sufficiently robust to certain violations of their assumptions.

El contraste de hipótesis acerca de dos proporciones supone que cada una de ellas se ha estimado mediante muestreo binomial, pero hay ocasiones en que interesa evaluar la hipótesis de que la probabilidad de éxito a medida que se repite una determinada tarea varía una vez que se ha obtenido el primer éxito. En estos casos, la probabilidad de éxito antes de que ocurra el primer éxito se estima mediante muestreo binomial negativo, en tanto que la probabilidad de éxito después del primer éxito se estima mediante muestreo binomial, y ambas estimaciones están relacionadas. En este trabajo se presentan procedimientos para contrastar dos hipótesis aplicables a esta situación. Una es la de que las dos probabilidades son iguales y tienen un determinado valor; la otra es más general y sólo expresa que las dos probabilidades son iguales. El comportamiento de estos dos contrastes en muestras finitas se analiza mediante simulaciones cuyos resultados muestran que en ambos casos se preserva adecuadamente la tasa nominal de error de tipo I. También se ha determinado mediante simulación los tamaños muestrales necesarios para detectar efectos grandes, medianos o pequeños con potencia suficiente. Finalmente, otro grupo de simulaciones muestra que ambos contrastes son suficientemente robustos ante violaciones de sus supuestos.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Apfelbaum, H. L., Apfelbaum, D. H., Woods, R. L., & Peli, E. (2008). Inattentional blindness and augmented-vision displays: Effects of cartoon-like filtering and attended scene. Ophthalmic and Physiological Optics, 28, 204217.CrossRefGoogle ScholarPubMed
Bain, L. J., & Engelhardt, M. (1992). Introduction to probability and mathematical statistics (2nd edition). Pacific Grove, CA: Duxbury.Google Scholar
Clark-Carter, D. (1997). The account taken of statistical power in research published in the British Journal of Psychology. British Journal of Psychology, 88, 7183.CrossRefGoogle Scholar
Cohen, J. (1992). A power primer. Psychological Bulletin, 112, 155159.Google Scholar
García-Pérez, M. A., & Núñez-Antón, V. (2004). Small-sample comparisons for goodness-of-fit statistics in one-way multinomials with composite hypotheses. Journal of Applied Statistics, 31, 161181.CrossRefGoogle Scholar
Larntz, K. (1978). Small-sample comparisons of exact levels for chi-squared goodness-of-fit statistics. Journal of the American Statistical Association, 73, 253263.CrossRefGoogle Scholar
The MathWorks, Inc. (2004). MATLAB: The language of technical computing. Natick, MA: Author.Google Scholar
Maxwell, S. E. (2004). The persistence of underpowered studies in psychological research: Causes, consequences, and remedies. Psychological Methods, 9, 147163.Google Scholar
Neisser, U., & Becklen, R. (1975). Selective looking: Attending to visually specified events. Cognitive Psychology, 7, 480494.Google Scholar
Numerical Algorithms Group (1999). NAG Fortran library manual, Mark 19. Oxford: Author.Google Scholar
Press, W. H., Flannery, B. P., Teukolsky, S. A., & Vetterling, W. T. (1986). Numerical recipes: The art of scientific computing. New York: Cambridge University Press.Google Scholar
Riefer, D. M., & Batchelder, W. H. (1991). Statistical inference for multinomial processing tree models. In Doignon, J.-P. & Falmagne, J.-C. (Eds.), Mathematical psychology: Current developments (pp. 313335). New York: Springer.Google Scholar
Rudas, T. (1986). A Monte Carlo comparison of the small sample behaviour of the Pearson, the likelihood ratio and the Cressie-Read statistics. Journal of Statistical Computation and Simulation, 24, 107120.CrossRefGoogle Scholar
Serlin, R. C., & Harwell, M. R. (2004). More powerful tests of predictor subsets in regression analysis under nonnormality. Psychological Methods, 9, 492509.CrossRefGoogle ScholarPubMed
Visual Numerics, Inc. (1997). IMSL math/library special functions. Houston, TX: Author.Google Scholar
Wolfram, S. (1992). Mathematica: A system for doing mathematics by computer (2nd edition). New York: Addison-Wesley.Google Scholar