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Question 1

What is the definition of statistics

Answer 1

Math used to describe and answer questions about a dataset

Question 2

What is a dataset

Answer 2

Organized facts that can generally be assembled in a table

Question 3

What are the two branches of statistics

Answer 3

Descriptive and inferential

Question 4

What is the descriptive branch of statistics

Answer 4

It summarizes the population or sample data

Question 5

How does one do inference in statistics

Answer 5

One makes conclusions about a population based on sample data

Question 6

What is a population in statistics

Answer 6

The entire potential dataset one is interested in

Question 7

What is a sample of a population in statistics

Answer 7

A subset of the unavailable dataset one is interested in

Question 8

Why use samples when doing statistics

Answer 8

It is more feasible and cheap

Question 9

How does one make sure that the sample data is representative of the population

Answer 9

Through random selection

Question 10

What is the scale of variable usefulness from worst to best

Answer 10

Nominal, ordinal, interval and ratio

Question 11

What is the properties of a nominal variable

Answer 11

They are non numerical but can be used for categorizing the data into larger groups that cannot be ordered in any obvious way such as a firms industry or an animals reproduction strategy

Question 12

What are the properties of ordinal variables

Answer 12

These can be ordered but does not have a set distance between the categories. Often used in subjective questions where for example 5 does not have to be five times as great as 1 so the variables cannot be used in arithmetic +*-/

Question 13

What properties do interval scale variables have

Answer 13

The data can be ranked and we can do meaningful arithmetic with it (addition and subtraction) although there is on meaningful zero so we cannot do multiplication, division and ratios. An example of this is time.

Question 14

What properties do ratio scale variables have

Answer 14

They can be fully compared and used in math. There is a meaningful zero. An example of a ratio is that 1kg bag is twice as heavy as a 500g bag.

Question 15

Which variable scales have fixed differences

Answer 15

Interval and ratio not nominal and ordinal

Question 16

What variable scales dont have a ranked order

Answer 16

Only nominal

Question 17

Wich is the only variable scale with an absolute zero

Answer 17

Ratio

Question 18

Which variable scales can you add subtract, multiply and divide

Answer 18

Add and subtract interval and ratio but only ratio can be multiplied and divided

Question 19

What is a continuous variable

Answer 19

An interval or ratio variable that can have the value of any real number aka anything that can be described as a decimal .0 or ratio 0/0 (math error). The possible variables are uncountably manny

Question 20

What are discrete variables

Answer 20

Variables that can only have the values of a finite, countable set if alternatives. Often dine out of connivance

Question 21

What are some types of unit/time data

Answer 21

Cross sectional, time series and panel data

Question 22

What is cross sectional data

Answer 22

N>1, T=1 many units observed during the same time

Question 23

What is a time series of data

Answer 23

N=1, T>1 observing the same unit at multiple points in time

Question 24

What is panel data

Answer 24

N>1,T>1 observing different units of data at different points in time

Question 25

What is the risk when presenting raw data

Answer 25

That it will overwhelm the watchers and not be very easy to understand

Question 26

What are the pros and cons of visualization in statistics

Answer 26

They make the data easier to understand but they can also be missleading

Question 27

What is a frequency distribution in statistics

Answer 27

The share of observations that fall into each category of a variable, can be used to give a value to the frequency at which a nominal variable apears

Question 28

What is meant by qualitative data

Answer 28

That it is nominal, aka misleadingly less useful

Question 29

What is meant by the modal answer

Answer 29

The answer that is most common

Question 30

What is a way to order continuous data

Answer 30

To use the intervals as categories. If there can be infinite alternatives between 0-1 you can simply have that as a category and save some paper

Question 31

What are the requirements when choosing intervals to compare when presenting a dataset

Answer 31

The interval categories must be mutually exclusive so no variable can appear in two as well as exhaustive aka all variables must fit into a category and for goodness sake it is best to make it limited and easy to understand

Question 32

What is cumulative relative frequency

Answer 32

The proportion of observations that falls below the upper limit of a particular interval

Question 33

What is a histogram

Answer 33

A series if rectangles in an x and y axis where x rectangle width represents the interval size and y rectangle hight represents the frequency

Question 34

What can be learned from a histogram about the variables

Answer 34

The spread and rough shape

Question 35

What is meant by a population being positively skewed

Answer 35

That the outliers are positive and that the frequency of the population is higher in the low intervals

Question 36

What is a scatterplot

Answer 36

A diagram that shows two variables of a population such as height and weight of gothwnburgers in one figure by having the x axis representing one variable and y the other to see if they are correlated by observing the pattern

Question 37

How can you introduce more categories in a scatterplot diagram

Answer 37

By having it represented by colors or symbols or some other dimension

Question 38

What is a line chart

Answer 38

A chart that draws a line by connecting consecutive observations of a numerical variable