Understanding EAMMi2

Background and codebook for the reduced EAMMi2 teaching data set.

Emerging Adulthood Measured at Multiple Institutions-2

Throughout this workbook, you will use the EAMMi2 data set to learn about statistical analyses and practice using R. The information that follows provides background about the EAMMi2 study and a codebook to help you navigate and understand the data file.

Important note

As you progress through this workbook, remember that the analyses and resulting conclusions are for demonstration purposes only.

What Is The EAMMi2 Study?

The EAMMi2 data set includes responses from undergraduate students at multiple institutions. Participants answered questions across several variables, including basic demographic questions, questions about personal experiences, and questions about well-being. The overarching goal of the study was to learn more about the psychological experiences of 18- to 29-year-olds, the age range associated with the transition from adolescence to adulthood.

The final sample size of respondents between the ages of 18 and 29 was 2,073. You can learn more about the EAMMi2 study and view the survey-with-codes PDF.

Our Data File

This workbook uses a reduced version of the original EAMMi2 data. The data file includes a subset of variables selected to allow you to conduct the types of analyses covered in Exploring Statistics.

The name of the data file used throughout this workbook is EAMMi2-REDUCED.csv. It is included in the starter files.

You are encouraged to save the starter folder somewhere on your computer where you can easily find it throughout your time in this course.

If you are new to R, begin with Choose Your Path and run scripts/00-open-and-check-data.R before working through the chapters.

Download the starter files here:

Download starter files

In the next sections, you will find a codebook for the data set. The codebook describes the variables used in the reduced data set and tells you how each variable is represented in the data file.

Opening The Data In R

The starter files include the data set and the R scripts. Open exploring-statistics-r.Rproj, then run the setup line at the top of a chapter script:

source("scripts/_setup.R")

The setup line creates a data frame named eammi. Most chapter scripts begin with this same line.

The data frame contains 39 variables.

Reading Coded Categories

Some variables use numbers to stand for categories. For example, the survey codes Adult as 1 = Yes, 2 = Maybe, and 3 = No; Gender as 1 = Male, 2 = Female, and 3 = Other; and Disability as 1 = Yes and 2 = No.

The chapter scripts will usually turn these numeric codes into readable labels before making tables or graphs. You do not need to memorize all of the codes. When a chapter uses a coded variable, the chapter will explain the codes needed for that analysis.

Missing Values

Missing values appear as NA in R. NA means that a value is not available for that person on that variable.

You can count missing values for a variable with:

sum(is.na(eammi$Stress))

Each chapter will point out missing-value checks when they matter for the analysis.

Survey Documentation

For more detail about the original survey questions and response options, see the EAMMi2 survey-with-codes PDF.

EAMMi2 Codebook

Variable	Brief description	Response options
`Duration`	How many minutes it took each participant to finish the survey	Duration automatically recorded from survey website
`Finished`	Whether or not the participant finished the survey	0 = no; 1 = yes
`FinanciallyInd`	Extent to which participant reported being financially independent	1 = no; 2 = somewhat; 3 = yes
`NoLongerHome`	Extent to which participant has moved out of parents’ home	1 = no; 2 = somewhat; 3 = yes
`MOA_ACH`	Extent to which participant has achieved markers of adulthood. Sample item: the extent to which the participant has settled into a long-term career.	20 items were rated 1 = no; 2 = somewhat; 3 = yes. The final score is the total across all provided markers of adulthood, with a possible range of 20-60.
`Adult`	Answer to “Are you an adult?”	1 = yes; 2 = maybe; 3 = no
`Exploration`	Responses to the Inventory of Dimensions of Emerging Adulthood. This 2-item subscale measured the extent to which this period of life was a time for exploration.	Each item was rated on a scale of 1 = strongly disagree to 4 = strongly agree. The subscale score represents the average rating across two items.
`Negativity`	Responses to the Inventory of Dimensions of Emerging Adulthood. This 2-item subscale measured the extent to which this period of life was a time for negativity.	Each item was rated on a scale of 1 = strongly disagree to 4 = strongly agree. The subscale score represents the average rating across two items.
`Identity`	Responses to the Inventory of Dimensions of Emerging Adulthood. This 2-item subscale measured the extent to which this period of life was a time for identity formation.	Each item was rated on a scale of 1 = strongly disagree to 4 = strongly agree. The subscale score represents the average rating across two items.
`BetweenStages`	Responses to the Inventory of Dimensions of Emerging Adulthood. This 2-item subscale measured the extent to which this period of life was a time for feeling between stages of life.	Each item was rated on a scale of 1 = strongly disagree to 4 = strongly agree. The subscale score represents the average rating across two items.
`Politics`	Self-reported political views	1 = extremely liberal to 7 = extremely conservative
`PoliticsDichotomous`	Self-reported political views, dichotomized into liberal and conservative categories	1 = liberal; 2 = conservative
`Party`	Self-reported political party affiliation	1 = extremely democrat to 7 = extremely republican
`PartyDichotomous`	Self-reported political party affiliation, dichotomized into democrat and republican categories	1 = democrat; 2 = republican
`SWLS`	Answers to the 5-item Satisfaction with Life Scale. Sample item: “In most ways my life is close to my ideal.”	Each item was rated on a scale of 1 = strongly disagree to 7 = strongly agree. The final SWLS score represents the sum of all 5 items, with a possible range of 5-35.
`Mindfulness`	Answers to the 15-item Mindful Attention Awareness Scale. Sample item: “I do jobs or tasks automatically, without being aware of what I’m doing.”	The final Mindfulness score is an average rating across items. Higher scores indicate greater mindfulness.
`Belonging`	Agreement with statement “I feel like I belong”	1 = not at all to 5 = very much
`SelfEfficacy`	Answers to the 10-item Generalized Self-Efficacy Scale. Sample item: “I can always manage to solve difficult problems if I try hard enough.”	Each item was rated on a scale of 1 = not at all true to 4 = exactly true. The final SelfEfficacy score is the sum across all 10 items, with a possible range of 10-40.
`SupportFriends`	Answers to the Perceived Social Support Scale. This subscale measured perceived support from friends. Sample item: “I can count on my friends when things go wrong.”	Items were rated on a scale of 1 = very strongly disagree to 7 = very strongly agree. This subscale is an average across relevant items.
`SupportFamily`	Answers to the Perceived Social Support Scale. This subscale measured perceived support from family.	Items were rated on a scale of 1 = very strongly disagree to 7 = very strongly agree. This subscale is an average across relevant items.
`SupportSpecial`	Answers to the Perceived Social Support Scale. This subscale measured perceived support from a “special someone.”	Items were rated on a scale of 1 = very strongly disagree to 7 = very strongly agree. This subscale is an average across relevant items.
`SocialSupport`	Answers to the Perceived Social Support Scale across friends, family, and a “special someone.”	SocialSupport represents the sum of all perceived social support items, with a possible range of 12-84.
`SMmaintain`	Items that assessed the extent to which participants reported using social media to maintain existing social connections.	Items were rated on a scale of 1 = never to 5 = a lot. This subscale is an average across relevant items.
`SMnewconnect`	Items that assessed the extent to which participants reported using social media to make new social connections.	Items were rated on a scale of 1 = never to 5 = a lot. This subscale is an average across relevant items.
`SMinformation`	Items that assessed the extent to which participants reported using social media to get or share information.	Items were rated on a scale of 1 = never to 5 = a lot. This subscale is an average across relevant items.
`SMtotal`	Overall use of social media across 11 items.	Items were rated on a scale of 1 = never to 5 = a lot. SMtotal represents the sum of all items, with a possible range of 11-55.
`USdream1`	Answer to “Do you believe in the importance of achieving the American Dream?”	1 = definitely not to 5 = yes, strongly
`USdream2`	Answer to “Do you believe you will be able to achieve the American Dream?”	1 = definitely not to 5 = yes, strongly
`Conflict`	Answer to “In the past two weeks, how often has someone gotten upset with you in response to something that you said or did?”	1 = not at all to 7 = constantly
`Symptoms`	13 items that assessed the extent to which participants were bothered by a variety of physical symptoms, such as stomach pain, back pain, and difficulty sleeping, during the past 4 weeks.	Each item was rated on a scale of 1 = not bothered at all to 3 = bothered a lot. This variable represents the sum of all 13 items, with a possible range of 13-39.
`Stress`	Answers to the 10-item Perceived Stress Scale. Sample item: “In the last month, how often have you felt confident about your ability to handle your personal problems?”	Each item was rated on a scale of 1 = never to 5 = very often. The final Stress score represents the sum of all 10 items, with a possible range of 10-50.
`IMPmarriage`	Importance placed on marriage as an eventual or current aspect of life.	Participants assigned a percentage from 0-100. They were instructed to answer `IMPmarriage`, `IMPparenting`, `IMPcareer`, and `IMPhobbies` so the total across all four aspects equaled 100%.
`IMPparenting`	Importance placed on parenting as an eventual or current aspect of life.	Participants assigned a percentage from 0-100. They were instructed to answer `IMPmarriage`, `IMPparenting`, `IMPcareer`, and `IMPhobbies` so the total across all four aspects equaled 100%.
`IMPcareer`	Importance placed on career as an eventual or current aspect of life.	Participants assigned a percentage from 0-100. They were instructed to answer `IMPmarriage`, `IMPparenting`, `IMPcareer`, and `IMPhobbies` so the total across all four aspects equaled 100%.
`IMPhobbies`	Importance placed on hobbies as an eventual or current aspect of life.	Participants assigned a percentage from 0-100. They were instructed to answer `IMPmarriage`, `IMPparenting`, `IMPcareer`, and `IMPhobbies` so the total across all four aspects equaled 100%.
`Gender`	Self-reported gender identity	1 = male; 2 = female; 3 = another identity
`Age`	Age of the participant, in years	Responses span ages 18-29
`Race`	Self-reported racial identity	1 = White; 2 = African American; 3 = Hispanic/Latinx; 4 = Asian/Pacific Islander; 5 = Native American; 6 = Another racial identity; 7 = Multiracial (2 selected); 8 = Multiracial (3 or more selected)
`Disability`	Self-identified disability status	1 = yes; 2 = no