Sequential analysis

Perform a sequential analysis to test two conditions.

Description

In statistics, sequential analysis or sequential hypothesis testing is statistical analysis where the sample size is not fixed in advance. Instead data is evaluated as it is collected, and further sampling is stopped in accordance with a pre-defined stopping rule as soon as significant results are observed. Thus a conclusion may sometimes be reached at a much earlier stage than would be possible with more classical hypothesis testing or estimation, at consequently lower financial and/or human cost.
REFERENCE:
I. Bross, Sequential medical plans. Biometrics. 1952; 8:186
 
Syntax: seqanalysis(x)
 
Inputs:
            X - Nx2 data matrix
Outputs:
            - Sequential analysis plots
 
 Example:
During a sperimentation between two terapies, two drugs A and B were administered to patients couples (one received A, the other B). A positive result in a patient by the drug is indicated by 1; a negative result by 0. Result are resumed in this table:
 
  Couple A B Note
    1 1 1 Non informative
    2 1 0 All for A
    3 0 0 Non informative
    4 1 0 All for A
    5 1 0 All for A
    6 1 1 Non informative
    7 0 1 All for B
    8 1 1 Non informative
    9 1 0 All for A
    10 1 0 All for A
    11 1 0 All for A
    12 1 1 Non informative
    13 1 0 All for A
    14 0 1 All for B
    15 0 0 Non informative
    16 1 0 All for A
    17 1 0 All for A
    18 1 0 All for A
    19 1 1 Non informative
    20 1 0 All for A
 
The algorithm will discard all non informative couple; then, it will
start to move along the chart. If it goes out the twilight zone, the sperimental plan can be stopped and non more couple will be required.

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• MATLAB release: MATLAB 7.6 (R2008a)

[Kay Zhang]

I cannot use it