Chapter 1 | Why Statistics?

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  • Next Week : Section, Lab 1 (Partial Key Posted), Chapter 2 Quiz, Lecture, Repeat.

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Agenda

  • 2:10 - 2:20 : Check-In & Announcements
  • 2:20 - 3:20 : Variables
  • 3:20 - 3:30 : Break #1
  • 3:30 - 4:00 : Linear Models and Predictions
  • 4:00 - 4:05 : Break #2
  • 4:05 - 4:30 : So you’re interested in going to graduate school?
  • 4:30 - 5:00 : DISCUSSION : Project Questions

Part 1 : Variables

Developing Research Questions from Real-Life

  • What are some real-life events that we want to better understand or change?
  • What are some research questions that we might develop based on real-life events?
  • How can we think about these questions using the ABCs of Psychology?
  • Is this a question about between-person or within-person variation?
  • How would you measure this variable with numbers? Do you think this is possible?

From Research Questions to Variables in R

Numeric Variables in R

Example In R : Creating Numeric Variables

num.var <- c(6,7,6,7,6,7,6,7)
hist(num.var)

String Variables in R

Example in R : Creating Non-Numeric Variables

cat.var <- c("string", "string", "string", "yarn")
cat.var <- as.factor(cat.var)
plot(cat.var)

ACTIVTY : Work on Lab 1, Question 1.

  1. Access Lab 1 (in the Week notes). Copy and paste the questions into a Word or Google Document.
  2. Open RStudio and a new RScript. Type some math into the Rscript, and send it to the console. THAT’S RIGHT. YOU ARE A PROGRAMMER. FRIEND OF COMPUTERS. CODE WIZARD.
  3. Work on Lab 1, Question 1 : Define two variables in R : one numeric, and one string. Note : you can use the data that we collected in class, or collect your own data (make sure each variable has at least ten data points). “Print” each variable in R, and paste the output as a screenshot. Then, graph the numeric variable as a “histogram” and the string variable as a “plot”. Below each graph, describe what you observe about the individuals in the dataset for each variable.

Break Time: Meet Back at

From Variables to Predictions (and Beyond)

Prediction & Power in Real Life

EXAMPLE : what will your bedtime be tonight?

  • Knowledge (what information did you use to make the prediction)?
  • Power (ways your predictions influence future behaviors)
  • Was The Prediction Valid?

Work on Lab Question 2.

What’s a prediction about people (or the world) that you made today? What information did you use to make this prediction? How did (or could) you use this prediction to influence outcomes? Were you valid in your predictions? Finally, write a linear model that defines the prediction (and information that you used) as a formula (e.g., DV ~ IV1 + IV2 + … + error).

Scientific Predictions

Psychological scientists seek to better understand variation, in order to help make valid predictions in ways that help exert power over our environments.

Knowledge of Neurons

Knowledge of Addiction

Link to NYT article. These data are a little dated; couldn’t find more recent data on this, but in reports to investors reports consistent growth in metrics like “ad impressions” and “daily active users”.

The Linear Model

RECAP : Definition and Examples

  • DV ~ IV1 + IV2 + IV3 + … + ERROR

    • list the variable that you want to predict (the DV)

    • list the variables that you think will help predict the DV (the IVs)

      • NOTE : you do not (and can not) account for EVERY variable in your linear model!

      • IN FACT : researchers are very specific about the variables they will include.

      • ERROR will capture all the other variables not in your model.

  • Example : Define a linear model to predict why people differ in the amount of screen time that they use (between or within-person differences)?

KEY IDEA : Linear Models Help Organize and Quantify Prediction

  • organize : a model specifies what information (IV) we think might help us predict the DV
  • quantify : when we add statistics to our model (much later!), we will see…

    • the direction of the prediction : is there a positive or negative relationship between the IV and the DV?

    • the “weight” of the prediction : how much does each IV help us predict the DV?

      • what is the “best” predictor in our model?

      • what is the “worst” predictor in our model?

    • the amount of error in our prediction : how well does the model as a whole help us predict individual scores? how well does the model generalize to “reality”?

A Real-Life Linear Model in the Wild.

From Prediction to Linear Models

  • I predict that attendance will improve students grades in the class.

~ attendance ~ grades + error

  • Write a model for your prediction (Lab 1, Q2)

Is science adequate?

“The revolutionary viewpoint of a movement which thinks it can dominate current history by means of scientific knowledge remains bourgeois…the utopian socialists, remaining prisoners of the mode of exposition of scientific truth, conceived this truth in terms of its pure abstract image….it is on the model of astronomy that the utopians thought they would discover and demonstrate the laws of society.” (82-83)

  • What makes sense / is confusing about this quote?
  • What are some problems with “the model of astronomy”?

Is science adequate?

“If you want knowledge, you must take part in the practice of changing reality. If you want to know the taste of a pear, you must change the pear by eating it yourself. If you want to know the structure and properties of the atom, you must make physical and chemical experiments to change the state of the atom. If you want to know the theory and methods of revolution, you must take part in revolution. All genuine knowledge originates in direct experience.” - Mao

Take this Exit Survey Now: tinyurl.com/onlinebyeintro

Next Time on Psych 101.

  • Attend Discussion Section & Complete Lab 1
  • Read Chapter 2 & take Quiz 2

So You Think You Want to Be a Researcher?

Getting Research Experience as an RA

RA = Research Assistant

Work You Do as an RA

  • work with data : transcribing data; behavioral coding data; recruiting and participants to collect data; setting up psychophysiological recordings; cleaning data; etc.

  • other opportunities to gain skills you can demonstrate :

    • reading & discussing papers

    • working with IRB (institutional review board - an ethics thing)

    • analyzing data → presenting research at a conference (poster) or submitting a paper for publication [your golden ticket]

    • general mentorship (how to apply to grad school; where to apply; who to talk to & e-mail; etc.)

    • NOTE : this work and these skills apply to other work outside of research applications [time management; coordinating schedules; juggling responsibilities; etc.]

What You Get Out of This

  • Course credit (hah), a letter of recommendation, ability to write about experiences that you have had (see above).

  • Vibes : is this [work or lab] for you?

    • do you enjoy the work? are you going to look forward to showing up and doing the work / fulfilling the commitment? 

    • are you working with a horrible monster?

      • not responsive

      • inconsistent work / no plan for your work

      • kind of a bully (emotionally abusive → stealing your work) 

    • or are you working with someone who is super cool and a positive influence on mentoring young minds!?!?! [YES!!!!]

Applying to Graduate School

  • You are applying to work on research with a specific professor(s) at a school.

    • Should have a sense of the topic you want to pursue.

    • Good to have a narrative about how your past work and studies have prepared you for this topic / demonstrate an enduring interest in the topic.

  • Independent Thesis / Research Project :

    • an official honors’ thesis

    • undergraduate research project (e.g., SURF; Psych 101!)

    • your own independent study / advanced work you did as an RA

  • Personal Statement : Experiences with Research You Can Write About

    • I’m fascinated by people…Over the last year, I worked on an independent research study to better understand….

    • Working as an RA; your research project; attending / presenting at a conference; etc.

  • 3-4 Letters of Recommendation : folks who can speak personally to your ability to do research.

  • Clinical Students : some kind of clinical internship / experience 😟

  • Talk to people who are doing the thing you want to be doing about their journey

The Academic Job Market

Academic Job Market Data [Source]
PhDs get jobs?
but not in academia…
$$$$$$$$