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Flashcards in Initial analysis of the data Deck (48)
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1

What are all R commands?

Functions

2

how do you get data into R

Read.table()
read.csv()

3

how do you get data out of R

write.csv()

4

what is nominal data?

names of things

5

what is ordinal data?

ordered names

6

what is interval data?

numeric with no true zero (Celsius)

7

what is ratio data?

numeric with true zero (kelvin)

8

which 2 data classifications are categorical or discreet?

nominal and ordinal

9

which 2 data classifications are continuous variables?

interval and ratio

10

what is a number?

can have decimals

11

what is a integer?

whole number

12

what is a character?

not a number

13

what is a vector?

set of values of the same data (combine function c() )

14

what is a list?

collection of different vectors or other data structures

15

what is a factor?

categorical variable
fixed set of values

16

what are arrays?

n-dimensional homogeneous data types

17

what are matrices?

2D and numeric

18

what is a data frame?

a list but all component vectors are same length

19

what is the R code for viewing the data?

head()
tail()

20

what is the r code for viewing a summary of the data?

summary()

21

what is the r code for computing basic statistics?

sd()
var()
range()
IQR()

22

What is the r code for the correlation?

cor()

23

what does visualisation give you?

more holistic picture of the data

24

what are summary statistics?

mean vs median
standard dev
quartiles
correlations

25

what is Anscombe's Quartet?

4 sets of data based on standard statistics

26

what does hist() mean in R?

Plot a histogram

27

what do missing values suggest?

dirty data

28

what is the best first visualisation of 2 variables?

scatter plots

29

what is a box and whisker plot?

a plot that shows the centre box of the data (50%)

30

why use a pairwise plot?

visually represent data relationships
examines relationship quickly