Hello, I have a series of x/y and a model. I can interpolate a new value of x using this model, but I get funny results if I give the y and look for the correspondent x: ``` > x = 1:10 > y = 2*x+15 > model <- lm(y~x) > predict(model, data.frame(x=7.5)) 1 30 > predict(model, data.frame(y=26)) 1 2 3 4 5 6 7 8 9 10 17 19 21 23 25 27 29 31 33 35 Warning message: 'newdata' had 1 row but variables found have 10 rows > data.frame(x=7.5) x 1 7.5 > data.frame(y=26) y 1 26 ``` what is the correct syntax? Thank you Luigi
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