## Writing text to the clipboard

I just realized that this is really easy as there exists in R function `writeClipboard()`

that copies character strings to the Windows clipboard!

writeClipboard("Hello") writeClipboard(as.character(1:10)) writeClipboard(sprintf("%.2f degrees", 1:10))

For the reverse operation of reading from the clipboard, two functions are available `getClipboardFormats()`

and `readClipboard()`

.

## Test of significance of linear regression slope

The examples below are for the common cases of a null hypothesis of *slope = 0* and *slope = 1*, but it should be clear how to test for for any arbitrary constant slope value expected *a priori* of examination of the data. The examples use a one-sided test, in many cases, a two-sided test should be used (e.g. if there is no *a priori* expectation of the deviation from the null hypothesis to be possible only in one direction). Source unknown, but certainly not of my authorship.

# cars data from R for this example data(cars) # linear regression fit cars.lm <- lm(dist ~ speed, data = cars) # extract slope estimate and its s.e. indexing by explanatory variable name my.slope <- summary(cars.lm)$coef["speed", c("Estimate", "Std. Error")] # extract degrees of freedom my.df <- summary(cars.lm)$df[2] # test against hypothesis of no response, i.e. slope = 0 t_value_zero <- my.slope["Estimate"] / my.slope["Std. Error"] dt(t_value_zero, df = my.df) / 2 # one sided test # test against hypothesis of 1:1 relationship, i.e. slope = 1 t_value_one <- (my.slope["Estimate"] - 1) / my.slope["Std. Error"] dt(t_value_one, df = my.df) / 2 # one sided test

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