Approximations 0.0, 0.5, 1.0, 1.5 so on untill 5

[bustosmiguel]

Hello,

I`m doing a rmse project, I have two vectors:

test_set: values 0.0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5 and 5
forecast_rating: values: 2.939235 3.738641 3.419572, etc.

But I need to create a forecast_rating_2 vector, but like test_set observations, like 0.0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5 and 5.

set.seed(1)
test_set %>%
left_join(edx1 %>%
group_by(movieId) %>%
summarise(fe = mean(rating - mu)), by = "movieId")
join <- test_set %>%
left_join(edx1 %>%
group_by(movieId) %>%
summarise(fe = mean(rating - mu)), by = "movieId")

forecast_rating <- mu + join$fe
forecast_rating

NOW RMSE:

mu <- mean(edx1$rating)
mu

set.seed(1)
difference <- test_set_r-forecast_rating
rmse <- sqrt(mean(difference^2))
rmse

0.94

(0.94 IS NOT GOOD, BECAUSE I NEED TO HAVE LESS THAN 0.9, so I think if I have a forecast_rating_2 vector, I will be more close to a 0.8 approximations.

Thank you!

Any recommendation will be very useful
thanks a lot

[bustosmiguel]

Hi guys, I found the function: ceiling()

forecast_rating2 <- ceiling(forecast_rating) is the solution

Cómo Redondear y Truncar en R

The bad new for me, is that I am more far that 0.8 hahaha
because now the result it`s :

sqrt(mean((test_set_r-forecast_rating2)^2))
[1] 1.102293