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### Best graphical representation of t-test data [duplicate]

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### How are regression, the t-test, and the ANOVA all versions of the general linear model?

How are they all versions of the same basic statistical method?
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### How to assess skewness from a boxplot?

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### Checking ANOVA assumptions

A few months ago I posted a question about homoscedasticity tests in R on SO, and Ian Fellows answered that (I'll paraphrase his answer very loosely): Homoscedasticity tests are not a good tool ...
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I have a small data set of 14 separate times to complete a task. However I am having difficulty finding an appropriate graph to use to graph the data. If the sample was larger I would use a box plot ...
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### One sided confidence interval for hypothesis testing

I'm having a hard time understanding how to use confidence intervals for hypothesis testing. I've seen examples to reject a null hypothesis, but don't understand how to use a one-sided confidence ...
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### T-test using only summary data in a box plot

I have the 5 number summary (min, Q1, Median, Q3, max) from two boxplots and wanted to test whether or not the averages of the groups in the two boxplots were significantly different. I would like ...
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I seem to recall one of my professors saying that error bars are completely uninformative when comparing repeated measures taken from a single group. Is that true? Surely many studies compute the ...
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I have two distributions of continuous, unpaired measurements. I would like to visualize the two distributions with a pair of histograms, counting measurements that fall over a bin's interval. Are ...
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When I look at scientific papers, bar charts I usually come to see are shown with mean +/- sem (standard error of the mean). As stated here, When standard error (SE) bars do not overlap, you ...
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### Can I use Standard deviation (in Excel error bars) with median in a graph?

I have a variable (vitamin D levels) that does not follow normal distribution. I wanted to plot its variation throughout a period of time. I used the median. However I wanted to add error bars in this ...