calculate whether regression coefficient is statistically significant in R
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I have results from a regression analysis conducted with another program and I would like to test with R whether they are significant. I know that ls.diag() calculates standard errors and t-tests for regression results, but it requires a very specific input format (i.e., the result of lsfit()), so I don't think I can use that. Is there any function in r that calculates standard errors and t-tests for regression analysis that allows me to simply give the relevant coefficients to the function by hand? 