# Connexions

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Inside Collection (Textbook):

Textbook by: Barbara Illowsky, Ph.D., Susan Dean. E-mail the authors

# Summary of Formulas

## Formula 1: Normal Probability Distribution

X X~ N ( μ , σ ) N(μ,σ)

μμ = the mean σσ = the standard deviation

## Formula 2: Standard Normal Probability Distribution

Z Z~ N ( 0 , 1 ) N(0,1)

zz = a standardized value (z-score)

mean = 0 standard deviation = 1

## Formula 3: Finding the kth Percentile

To find the kth percentile when the z-score is known: k = μ + ( z ) σ k=μ+(z)σ

## Formula 4: z-score

z = x - μ σ z= x - μ σ

## Formula 5: Finding the area to the left

The area to the left: P ( X < x ) P ( X x )

## Formula 6: Finding the area to the right

The area to the right: P ( X > x ) = 1 - P ( X < x ) P ( X x ) =1- P ( X x )

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'My Favorites' is a special kind of lens which you can use to bookmark modules and collections. 'My Favorites' can only be seen by you, and collections saved in 'My Favorites' can remember the last module you were on. You need an account to use 'My Favorites'.

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##### Lenses

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##### What is in a lens?

Lens makers point to materials (modules and collections), creating a guide that includes their own comments and descriptive tags about the content.

##### Who can create a lens?

Any individual member, a community, or a respected organization.

##### What are tags?

Tags are descriptors added by lens makers to help label content, attaching a vocabulary that is meaningful in the context of the lens.

| External bookmarks

#### Module to:

My Favorites (?)

'My Favorites' is a special kind of lens which you can use to bookmark modules and collections. 'My Favorites' can only be seen by you, and collections saved in 'My Favorites' can remember the last module you were on. You need an account to use 'My Favorites'.

| A lens I own (?)

#### Definition of a lens

##### Lenses

A lens is a custom view of the content in the repository. You can think of it as a fancy kind of list that will let you see content through the eyes of organizations and people you trust.

##### What is in a lens?

Lens makers point to materials (modules and collections), creating a guide that includes their own comments and descriptive tags about the content.

##### Who can create a lens?

Any individual member, a community, or a respected organization.

##### What are tags?

Tags are descriptors added by lens makers to help label content, attaching a vocabulary that is meaningful in the context of the lens.

| External bookmarks