R interview questions part 26
R interview questions part 26
Take as many assements as you can to improve your validate your skill rating
Total Questions: 20
1. What plot(s) are used to view the linear regression?
Correct Answer is : Scatterplot, Boxplot, Density plot
2. In lm(response ~ terms), terms specification of the form “first*second” is same as __________
Correct Answer is : first+second+first:second
3. ________ is an incredibly powerful tool for analyzing data.
Correct Answer is : Linear regression
4. The square of the correlation coefficient r 2 will always be positive and is called the ________
Correct Answer is : Coefficient of determination
5. Predicting y for a value of x that’s outside the range of values we actually saw for x in the original data is called___________
Correct Answer is : Extrapolation
6. What is predicting y for a value of x that is within the interval of points that we saw in the original data called?
Correct Answer is : Intra polation
7. Analysis of variance in short form is?
Correct Answer is : ANOVA
8. ______ is a simple approach to supervised learning. It assumes that the dependence of Y on X1, X2, . . . Xp is linear.
Correct Answer is : Linear regression
9. Although it may seem overly simplistic, _______ is extremely useful both conceptually and practically.
Correct Answer is : Linear regression
10. When there are more than one independent variables in the model, then the linear model is termed as _______
Correct Answer is : Multiple Linear model
11. The parameter β0 is termed as intercept term and the parameter β1 is termed as slope parameter. These parameters are usually called as _________
Correct Answer is : Regression coefficients
12. The sum of squares of the difference between the observations and the line in the horizontal direction in the scatter diagram can be minimized to obtain the estimates is generally called?
Correct Answer is : reverse regression method
13. ______ regression method is also known as the ordinary least squares estimation.
Correct Answer is : Direct
14. __________ refers to a group of techniques for fitting and studying the straight-line relationship between two variables.
Correct Answer is : Linear regression
15. In order to calculate confidence intervals and hypothesis tests, it is assumed that the errors are independent and normally distributed with mean zero and _______
Correct Answer is : Variance
16. What do we do the curvilinear relationship in linear regression?
Correct Answer is : ignore
17. When hypothesis tests and confidence limits are to be used, the residuals are assumed to follow the __________distribution.
Correct Answer is : Normal
18. ________ loop over a list and evaluate a function on each element
Correct Answer is : apply()
19. __________ function is same as lapply in R
Correct Answer is : sapply()
20. Which of the following is multivariate version of lapply ?
Correct Answer is : mapply()
