Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biostatistics > Lab 2: Means and Beyond- More Descriptive Statistics, Defining and Making Your Own Functions That Can be Reused, and Using R Packages + Lab 3: Confidence Interval of a Proportion > Flashcards

Lab 2: Means and Beyond- More Descriptive Statistics, Defining and Making Your Own Functions That Can be Reused, and Using R Packages + Lab 3: Confidence Interval of a Proportion Flashcards

(55 cards)

Start Studying
1
Q

Can the letter c be used both as a built-in R function and object?

A

YES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What will determine whether the letter c is used a built-in R function or as an object?

A

Its location in the code!

- If it precedes the arrow, it's being defined as an object
- If it comes after the arrow, it's being used as a built-in R function
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

If you define an object and then try to define it again with the same letter, what will happen? How would this effect the mean/median

A
  • That object will be overwritten and will now be replaced/ contain the new data set.
  • The mean/ median will change to be representative of the new data set
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

An object is always determined by what?

A

Its newest definition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are two ways in which an exponent can be inputted into R?

A

Using either the carrot(EX: 10^5) or e method (1e+5) with positive (+) numbers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are two ways in which an exponent can be inputted into r?

A

Using either the carrot(EX: 10^5) or e method (1e+5) with negative (-) numbers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

If there is no built-in R function for performing certain statistical analyses, what can you do?

A

Either define your own R function or download reproducible codes in some fundamental units made by other people called R packages.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is another good way to think of an R package?

A

Like an extra toolbox that contains a variety of tools to add to built- in tools that come with base R

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Do people usually upload the packages they developed and share them with all R users?

A

YES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the two ways in which we can install an R package?

A

Type in the R command or use the pull- down manual

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the function you should use to install an R package?

A

install. packages(“ “)

- With a lowercase i and packages being plural

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the “CRAN mirrors?”

A

Mirror sites with the repositories of the package

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What will happen if you try to install a package into base R using command lines and what do you have to do?

A

The “CRAN mirrors” window will pop up and you’ll have to scroll down and highlight to select “USA (PA 1)” to install?

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What will happen if you try to install a package into the code editor R Studio using command lines and what do you have to do?

A

The “CRAN mirrors” window will NOT pop up and you won’t have to do anything else, as the package will automatically be installed after hitting enter/return.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How do you install an R package in base R, using the pull- down manual?

A

Follow the selection: “Packages”-> Install Package(s)-> select “raster”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How do you install an R package in base R, using the pull- down manual?

A
  • There is a tab named “Packages” in the lower-right quadrant/panel, click it
  • Click “install”
  • In the pop-up window, type “raster” in the space below the sentence that reads “Packages separate multiple with space or comma)”
  • Click “install”
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What function must you use to activate a newly installed R package?

A

library(name of package) with a lowercase l and NO QUOTATION MARKS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

If you stay in the same R session, do you need to reactive the newly installed R package before using it again?

A

NO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

If you close and restart a new R session, do you need to reactivate the newly installed R package before attempting to use it again?

A

YES

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What package are the geometric and harmonic mean function found in?

A

The “psych” package

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What package is the coefficient of variation function found in?

A

The “raster” package

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What function would you use to find the geometric mean?

A

geometric.mean( )

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What function would you use to find the harmonic mean?

Study These Flashcards
A

harmonic.mean( )

24
Q

What function would you use to find the coefficient of variation (CV)?

25
What is the CV calculated by the function "cv( )" from the package "raster" really? As a result, how should it be reported?
It's the percentage of the actual CV, so it should be reported either with a % or as the decimal version of that percentage
26
What function would you use to determine the MAD of a data set?
>mad(object,constant= )
27
When trying to determine the MAD of a data set and you're using the command line ">mad(object,constant= ), what must you specify your constant as if you data set is SMALL`
1
28
What are the two ways in which you can find the interquartile range of a data set in R?
Use the information from the 5 number summary or use the built- in R function, "IQR( )"
29
When trying to determine the interquartile range of a data set and the data set is small, what may happen and what do we do to avoid this?
When the data set is small, different methods may give us different results, so we must specify what method using the argument "type="
30
When trying to determine the interquartile range of a data set, if you don't specify what method to use with the argument "type=", which one will R chose by default?
"type=7"
31
When the confidence interval is 95%, the z score is?
1.96
32
What does w stand for?
The margin of error
33
How do we find the upper CL?
p'+w
34
How do we find the lower CL?
p'-w
35
What are the 4 ways in which you could find the CI of a proportion in R?
Performing step-by-step calculations in R, the Modified Wald Method, Standard Wald Method, Exact Method
36
Out of the 4 ways to calculate the CI of a proportion in R, which is the most accurate and which is the easiest/hardest to do by hand?
- The Standard Wald Method is easiest to compute by hand - The Exact Method is hardest to do by hand - The Modified Wald Method is not much harder to do than the Standard Wald Method, but it's MUCH more accurate
37
Is the CI calculated using the Modified Wald Method and the Standard Wald Method going to be the same?
NO, they'll be slightly different
38
Which built-in R function is used for the Modified Wald Method?
add4ci( )
39
Which built- in R function is used for the Standard Wald Method
addz2ci( )
40
Which built in R function is used for the Exact Method?
exactci( )
41
What is the disadvantage of using the Exact Method?
It can't be easily computed by hand and calculates a CI that is sometimes wider than necessary
42
If we increase the confidence level, what will happen to the CI?
It will become wider
43
If we decrease the confidence level, what will happen to the CI?
It will become narrower
44
What is the relationship between the confidence level and the CI?
It's a direct relationship: As the confidence level increase, the CI becomes wider and as the confidence level decreases, the CI becomes narrower.
45
When should the Rule of Three be used?
When the numerator in s/n AKA the number of successes is 0
46
When should the Rule of Five be used?
When the numerator in s/n AKA the number of successes is 1
47
When should the Rule of Seven be used?
When the numerator in s/n AKA the number of successes is 2
48
When you apply the Rule of Three, Five, or Seven, what is always the lower confidence limit?
0
49
When can the Rule of Three, Five, and Seven be applied?
When the success # is v small and the sample size is large.
50
You can only take shortcuts like the Rule of Three, Five, and Seven to estimate the CI when the confidence interval is what?
95%
51
What does every aspect of this code mean: >add4ci(x=16,n= 565,conf.level = 0.95) ?
- Function “add4ci” is for the Modified Wald Method - x or s is the number of successes (s) -> Would change depending on what method being used! - n is the number of experiments (n) - Conf.level equals the confidence level and expresses it in proportions
52
The functions for the Modified Wald Method, Standard Wald Method, and Exact Method are found under what packages?
"PropCIs" and "devtools"
53
What line of code can be used to set p' after defining s and n when trying to determine the CI of a proportion ?
>pprime
54
What line of code can be used to set w after defining pprime(p'), s, and n when trying to determine the CI of a proportion?
>w
55
The result from the Rule of Three is closer to the result of which method?
Exact Method

Biostatistics (4 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions