Exploratory Data Analysis

Question 1

Data that are expressed on a numerical scale is what data type?

Answer 1

numeric

Question 2

Data that can take only a specific set of values representing a set of possible categories (enums, enumerated, factors, nominal) are what data type?

Answer 2

categorical

Question 3

Cite the two numerical data types

Answer 3

continuous and discrete

Question 4

Cite the two categorical data types

Answer 4

binary and ordinal

Question 5

Data that can take on any value in an interval (float, numeric)

Answer 5

continuous

Question 6

Data that can take only integer values, such as counts

Answer 6

discrete

Question 7

True or False

Data typing in software acts as a signal on how to process the data

Answer 7

True

Question 8

Rectangular data (like a spread sheet) is the basic structure for statistical and machine learning models, cite the structure?

Answer 8

dataframe

Question 9

A column (series) within a table is commonly referred to as a _______?

Answer 9

feature

Question 10

Many data science projects involve predicting an ______?

Answer 10

outcome (dependent variable, response, target, output)

Question 11

A row in a table is referred to as a ______?

Answer 11

record

Question 12

What is the sum of all values divided by the number of values

Answer 12

mean

Question 13

The sum of all values times a weight divided by the sum of the weights

Answer 13

weighted mean

Question 14

The value such that one-half of the data lies above and below

Answer 14

median

Question 15

The value such that P percent of the data lies below

Answer 15

percentile (quantile)

Question 16

The value such that one-half of the sum of the weights lies above and below the sorted data

Answer 16

weighted median

Question 17

The average of all values after dropping a fixed number of extreme values

Answer 17

trimmed mean (truncated mean)

Question 18

Not sensitive to extreme values

Answer 18

Robust (resistant)

Question 19

What is a data value that is very different from most of the data?

Answer 19

Outlier (extreme value)

Question 20

The difference between the observed values and the estimate of location?

Answer 20

deviations

Question 21

The sum of squared deviations from the mean divided by n-1 where n is the number of data values.

Answer 21

variance

Question 22

The square root of the variance

Answer 22

standard deviation

Question 23

The mean of the absolute values of the deviations from the mean (L1-norm, Manhattan norm)

Answer 23

mean abs deviation

Question 24

The mean of the absolute values of the deviations from the median

Answer 24

median abs deviation from the median

Question 25

The difference between the largest and smallest value in a data set.

Answer 25

range

Question 26

Metrics based on the data values sorted from smallest to largest (ranks)

Answer 26

order statistics

Question 27

The value such that P percent of the values take on this value or less and (100-P) percent take on this value or more

Answer 27

percentile

Question 28

The difference between the 75th percentile and the 25th percentile (IQR)

Answer 28

interquartile range

Question 29

The basic metric for location is the ____, but it can be sensitive to extreme values _____?

Answer 29

mean, outliers

Question 30

Location is one dimension in summarizing a _______?

Answer 30

feature

Question 31

A second dimension, variability (dispersion) measures?

Answer 31

whether the data values are tightly clustered or spread out.

Question 32

What are the objectives being performed during the exploratory data analysis phase (EDA)?

Answer 32

``` elements of structured data estimates of location estimates of variability(dispersion metrics) exploring the data distribution exploring binary and categorical data correlation exploring two or more variables ```

Question 33

estimates of location can be describe by?

Answer 33

mean, median and robust estimates.

Question 34

What is being described in estimates of location?

Answer 34

the mean, median and robust estimates.

Question 35

What is being described in the estimates of variability?

Answer 35

standard deviation and related estimates | estimates based on percentiles

Question 36

What is being described when exploring the data distributions?

Answer 36

percentiles and boxplots frequency tables and histograms density plots and estimates

Question 37

What is meant by exploring binary and categorical data?

Answer 37

mode, expected value, probability

Question 38

What describes exploring two or more variables?

Answer 38

hexagon binning and contours (plotting numeric vs numeric data) two categorical variables visualizing multiple variables

Question 39

Give an example of a numerical continuous data?

Answer 39

weight (which can be infinitely divided)

Question 40

Give an example of a numerical discrete data?

Answer 40

year of birth (numerical data that can't be divided)

Question 41

Give an example of a categorical binary value? (only two options)

Answer 41

a brand of camera, Sony

Question 42

Give an example of a categorical ordinal value? (ordinal meaning order)

Answer 42

data where the order of it matters

Question 43

Pandas stands for what?

Answer 43

panel data