終於，sjPlot套件的作者為view_df加上了「加權」功能

Published by 劉正山, October 18th, 2015

Version 1.8.4

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General:

* Improved encoding detection for `sjt`-functions.

Changes to functions:

* Predictor grouping with argument `group.pred` now also works for `sjt.lmer` and `sjt.glmer` (in certain cases may be buggy, so `group.pred` defaults to `FALSE`).

* Argument `vars` in `sjp.lmer` and `sjp.glmer` now also applies when plotting estimates (`type = "fe"` or `type = "re"`).

* `view_df_` gets a `weightBy` argument.

* Argument `showCI` in `sjp.int` accepts numeric values for `type = "eff"`, indicating the confidence interval value.

* Minor improvements to `view_df`, `sjp.lm` and `sjp.lmm`.

* Improved accuracy of computation of skewness value in `sjt.itemanalysis`.

Bug fixes:

* Fixed bug where in certain cases, ordered factors were not labelled correctly in `sjp.frq`.

* Value labels were not shown in `sjp.aov1`.

* Axis labels were reversed in `sjp.pca` for `type = "bar"`.