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 — reference:ft_statfun_actvsblt [2018/08/23 14:43] (current) Line 1: Line 1: + =====  FT_STATFUN_ACTVSBLT ===== + + Note that this reference documentation is identical to the help that is displayed in MATLAB when you type "help ft_statfun_actvsblT"​. + + <​html><​pre>​ + <​font color=green>​FT_STATFUN_ACTVSBLT​ calculates the activation-versus-baseline T-statistic on the + biological data (the dependent variable), using the information on the independent + variable (ivar) in design. + + Note that it does not make sense to use this test statistic when baseline + correction was performed by subtracting the mean of the baseline period from the + whole data (for ERP data) or by dividing by the mean (for TFR data). If baseline + correction is desired, you should subtract the full baseline and activation period. + + Use this function by calling one of the high-level statistics functions as + [stat] = ft_timelockstatistics(cfg,​ timelock1, timelock2, ...) + [stat] = ft_freqstatistics(cfg,​ freq1, freq2, ...) + [stat] = ft_sourcestatistics(cfg,​ source1, source2, ...) + with the following configuration option + cfg.statistic = '​ft_statfun_actvsblT'​ + + Configuration options + cfg.computestat ​   = '​yes'​ or '​no',​ calculate the statistic (default='​yes'​) + cfg.computecritval = '​yes'​ or '​no',​ calculate the critical values of the test statistics (default='​no'​) + cfg.computeprob ​   = '​yes'​ or '​no',​ calculate the p-values (default='​no'​) + + The following options are relevant if cfg.computecritval='​yes'​ and/or + cfg.computeprob='​yes'​. + cfg.alpha = critical alpha-level of the statistical test (default=0.05) + cfg.tail ​ = -1, 0, or 1, left, two-sided, or right (default=1) + cfg.tail in combination with cfg.computecritval='​yes'​ + determines whether the critical value is computed at + quantile cfg.alpha (with cfg.tail=-1),​ at quantiles + cfg.alpha/2 and (1-cfg.alpha/​2) (with cfg.tail=0),​ or at + quantile (1-cfg.alpha) (with cfg.tail=1). + + Design specification + cfg.ivar ​ = row number of the design that contains the labels of the conditions that must be + compared (default=1). The first condition, indicated by 1, corresponds to the + activation period and the second, indicated by 2, corresponds to the baseline period. + cfg.uvar ​ = row number of design that contains the labels of the units-of-observation (subjects or trials) + (default=2). The labels are assumed to be integers ranging from 1 to + the number of units-of-observation. + + See also <​font color=green>​FT_TIMELOCKSTATISTICS,​ <​font color=green>​FT_FREQSTATISTICS​ or <​font color=green>​FT_SOURCESTATISTICS​ +