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Automatic Analysis of Series of Trials

Select menu: Stats | Mixed Models (REML) | Automatic Analyses | Series of Trials

This dialog provides facilities for the automatic analysis of a series of trials using the method of residual maximum likelihood (REML), which is also sometimes called restricted maximum likelihood. The data should be supplied in a single variate with factors to specify the experiments, and optionally the replicates, blocks, rows and columns of a rectangular grid, and plots within the trials.

If the rows and columns are not equally spaced or a linear trend is being estimated, then row and column coordinates must be provided to use correlation models that take into account unequal spacing, or to allow the linear trends to be estimated across the whole trial.

  1. After you have imported your data, from the menu select 
    Stats | Mixed Models (REML) | Automatic Analyses | Series of Trials.
  2. Fill in the fields as required then click Run.

You can set additional Options then after running, you can save the results by clicking Save.

The VASERIES procedure is used to fit the model automatically for each experiment, and the VAMETA procedure is used to fit the model over all trials. See the help on these procedures for more details on how this is done.

Available data

This lists data structures appropriate to the current input field. The contents will change as you move from one field to the next. Double-click on a name to copy it to the current input field or type the name.

Y-variate

Specifies a variate containing the data values.

Experiments

Factor specifying the experiments or trials in the series.

Replicate factor

An optional factor specifying the replicates within each trial.

Block factor

An optional factor specifying the blocks in the trial. If only some trials are blocked, then entries in this should be missing for the trials not blocked.

Row factor

An optional factor specifying the rows in the layout within each trial. If only some trials are in a rectangular grid, then entries in this should be missing for the trials not having rows and columns.

Row coordinates

An optional variate or factor specifying the spacing of rows. If the layout is irregular or a linear trend is being tried, this must be specified.

Column factor

An optional factor specifying the columns in the layout in each trial. If only some trials are in a rectangular grid, then entries in this should be missing for the trials not having rows and columns.

Column coordinates

An optional variate or factor specifying the spacing of columns. If the layout is irregular or a linear trend is being tried, this must be specified.

Plot factor

An optional factor specifying the plots in the trials.

Fixed model

The fixed model terms describe imposed treatment factors and covariates for which the effect of specified levels or values are of interest. The fixed model is described using a formula, which can combine main effects and interactions of factors and also covariates.

Additional random terms

The random model is generally used to describe those factors for which the values present in an experiment can be considered drawn from some large homogeneous population. This specifies terms extra to the variance components defined by the replicates, blocks, rows and columns factors. The additional terms are described using a formula, which can combine main effects and interactions of factors and also covariates.

Operators

This provides a quick way of entering operators in the fixed and random model formulas. Double-click on the required symbol to copy it to the current input field. You can also type in operators directly. See model formula for a description of each.

Action buttons

Run Run the analysis.
Cancel Close the dialog without further changes.
Options Opens a dialog where additional options and settings can be specified for the analysis.
Defaults Reset options to the default settings. Clicking the right mouse on this button produces a shortcut menu where you can choose to set the options using the currently stored defaults or the Genstat default settings.
Save Opens a dialog where you can save results from the analysis.
Predict Allows you form predictions based on the current model.
Further output Opens a dialog for specifying further output from the analysis and displaying residual and means plots.
Explore fixed model Opens a dialog for exploring the fixed model from the analysis. This allows you try different subsets of the fixed model to see which terms are important.

Action Icons

Pin Controls whether to keep the dialog open when you click Run. When the pin is down  the dialog will remain open, otherwise when the pin is up  the dialog will close.
Restore Restore names into edit fields and default settings.
Clear Clear all fields and list boxes.
Help Open the Help topic for this dialog.

See also

Updated on October 28, 2020

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