Abstract
The task of monitoring for a change in the mean of a sequence of Bernoulli random variables has been widely studied. However most existing approaches make at least one of the following assumptions, which may be violated in many real-world situations: (1) the pre-change value of the Bernoulli parameter is known in advance, (2) computational efficiency is not paramount, and (3) enough observations occur between change points to allow asymptotic approximations to be used. We develop a novel change detection method based on Fisher’s exact test which does not make any of these assumptions. We show that our method can be implemented in a computationally efficient manner, and is hence suited to sequential monitoring where new observations are constantly being received over time. We assess our method’s performance empirically via using simulated data, and find that it is comparable to the optimal CUSUM scheme which assumes both pre- and post-change values of the parameter to be known.
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References
Agresti A (1992) A survey of exact inference for contingency tables. Stat Sci 7: 131–153
Basseville M, Nikiforov IV (1993) Detection of Abrupt Change Theory and Application. Prentice Hall
Braun WJ (1999) Run length distributions for estimated attributes charts. Metrika 50: 121–129
Chang TC, Gan FF (2001) Cumulative sum charts for high yield processes. Stat Sin 11: 791–805
Chen J, Gupta A (1997) Testing and locating variance changepoints with application to stock prices. J Am Stat Assoc 92: 739–747
Domingos P, Hulten G (2003) A general framework for mining massive data streams. J Comput Graph Stat 12: 945–949
Hawkins DM, Qiu PH, Kang CW (2003) The changepoint model for statistical process control. J Qual Technol 35: 355–366
Hawkins DM, Zamba KD (2005) A change-point model for a shift in variance. J Qual Technol 37: 21–31
Hinkley D, Hinkley E (1970) Inference about change-point in a sequence of binomial variables. Biometrika 57: 477–488
Lorden G (1971) Procedures for reacting to a change in distribution. Ann Math Stat 42: 1897–1908
Montgomery DC (2005) Introduction to Statistical Quality Control. Wiley
Nelson LS (1994) A control chart for parts-per-million nonconforming items. J Qual Technol 26: 239–240
Pettitt AN (1980) A simple cumulative sum type statistic for the change-point problem with zero-one observations. Biometrika 67: 79–84
Reynolds M, Stoumbos Z (1999) A CUSUM chart for monitoring a proportion when inspecting continuously. J Qual Technol 31: 87–108
Ross GJ, Adams NM, Tasoulis DK, Hand DJ (2011) A Nonparametric change point model for streaming data. Technometrics 53: 379–389
Woodall W (1997) Control charts based on attribute data: bibliography and review. J Qual Technol 29: 172–183
Yeh AB, Mcgrath RN, Sembower MA, Shen Q (2008) EWMA control charts for monitoring high-yield processes based on non-transformed observations. Int J Prod Res 46: 5679–5699
Zhou C, Zou C, Zhang Y, Wang Z (2009) Nonparametric control chart based on change-point model. Stat Pap 50: 13–28
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Ross, G.J., Tasoulis, D.K. & Adams, N.M. Sequential monitoring of a Bernoulli sequence when the pre-change parameter is unknown. Comput Stat 28, 463–479 (2013). https://doi.org/10.1007/s00180-012-0311-7
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DOI: https://doi.org/10.1007/s00180-012-0311-7