R interview questions part 39
R interview questions part 39
Take as many assements as you can to improve your validate your skill rating
Total Questions: 20
1. What would be the output of the following code ? > x <- as.Date("2012-03-01") > y <- as.Date("2012-02-28") > x-y
Correct Answer is : Time difference of 2 days
2. Which of the following code represents internal representation of a Date object ?
Correct Answer is : unclass(as.Date(“1970-01-02”))
3. What would be the output of the following code ? > x <- as.POSIXct("2012-10-25 01:00:00") > y <- as.POSIXct("2012-10-25 06:00:00", tz = "GMT") > y-x
Correct Answer is : Time difference of 1 hour
4. Which of the following method make vector of repeated values ?
Correct Answer is : data()
5. Which of the following finds the position of a quantile in a dataset ?
Correct Answer is : quantile()
6. Which of the following function cross-tabulate tables using formulas ?
Correct Answer is : all of the mentioned
7. Which of the following groups find the correlation matrix ?
Correct Answer is : factor.model
8. which of the following statement make a mosaic plot ?
Correct Answer is : mosaicplot()
9. Which of the following compute proportions from a contingency table ?
Correct Answer is : prop.table()
10. Which of the following is lattice command for producing a scatterplot ?
Correct Answer is : xyplot()
11. Which of the following builds empirical cumulative distribution function ?
Correct Answer is : ecdf()
12. Which of the following is used to view dataset in a spreadsheet-type format ?
Correct Answer is : View()
13. ________ function carries out a chi-square test.
Correct Answer is : chisq.test()
14. Which of the following adds marginal sums to an existing table ?
Correct Answer is : prop.table()
15. Which of the following lists names of variables in a data.frame ?
Correct Answer is : quantile()
16. Which of the following is tool for chi-square distributions ?
Correct Answer is : pnorm
17. Which of the following groups values of a variable into larger bins ?
Correct Answer is : cut
18. Which of the following determine the least-squares regression line ?
Correct Answer is : lm
19. Which of the following is tool for checking normality ?
Correct Answer is : qqline()
20. Which of the following is lattice command for producing boxplots ?
Correct Answer is : bwplot()
