Week 2

Sunday, Monday, Tuesday; midnight, noon; 5.4,5.6,5.8,60 are what?

Level (s) of a variable

tanning changes your brain

causal claim

teenage pot smoking affects intelligence

causal claim

What are the following terms 'needs to demonstrate or 'does not need to demonstrate'? Exercise came before the measurement of stress. amount of expertise goes up as stress goes down. no other explanations for why exercise is linked to stress.

'needs to demonstrate

Sweetened drink linked to depression risk; depression in elderly may predict dementia folic acid is tied to more advanced toddler talk

Association claims

Researchers are investigating whether elementary school children differ significantly in their critical-thinking ability at various ages by measuring such differences between first, second, and third graders. Each student at Cedar Elementary School receives the same intelligence test, and the researchers then compare their scores. The researchers also record the age of each student, to see whether age is linked to performance on the test. Only participants whose first language is English are studied.

Constant: 1. middle school location 2. Student primary language 3. type of intelligence test Variable: 1. Student age2. Student grade level3. Intelligence scores

Researchers want to know whether the age at which people begin using a cell phone is associated with their level of extroversion. The researchers will examine the number of people that participants interact with in a day. Which of the following words describe "extroversion" in the context of this study? - measured - conceptual - variable - manipulated - operational - constant

Describing "Extroversion" measured conceptual variable Not Describing "Extroversion" manipulated operational constant

While reading news online, Johan comes across the headline "When stress is increased, men rush ahead, women more cautious." (The article is based on a study conducted by Lighthall et al., 2011.) In this study, researchers asked men and women to perform a decision task as many times as possible in a set period, in either a stressed or an unstressed condition. In the unstressed condition, men and women performed similarly. However, in the stressed condition, the number of decision tasks that men performed increased while the number that women performed decreased. Identify each variable from the study as either measured or manipulated.

Measured: Gender of participant, # of decision tasks performed Manipulated: amount of stress

Which types of validity were not established in this study, and which were reasonably met? A recent study investigated whether watching cat videos online causes viewers to have less stress. The study recruited a diverse sample of online participants and had them watch a video of kittens. The participants were then given a 5-item questionnaire about their current stress levels. Participants seemed to have less stress after watching the video, and a statistical test showed a strong effect.

Not established: internal Reasonably: external, construct, statistical

Which of the following items are operational definitions of stress? a measurement of the amount of a "fight or flight" hormone in saliva; a 10-item questionnaire asking participants about feeling stressed in the past week; mental tension; feelings of anxiousness and pressure worry about school

Operational Definition(s) of Stress a measurement of the amount of a "fight or flight" hormone in saliva a 10-item questionnaire asking participants about feeling stressed in the past week Not Operational Definition(s) of Stress mental tension feelings of anxiousness and pressure worry about school

Identify each item as either an operational or a conceptual variable. Identify each item as either an operational or a conceptual variable. type of beverage consumed (caffeinated versus caffeine-free) number of text messages sent per day tolerance for spicy food effectiveness of study method memory

Operational Variable(s) type of beverage consumed (caffeinated versus caffeine-free) number of text messages sent per day Conceptual Variable(s) tolerance for spicy food effectiveness of study method memory

Identify the true and false statements about the statistical validity of association claims. - A study that finds a 55% difference between groups demonstrates a stronger association than a study that finds a 10% difference between groups. - Confidence intervals reflect the precision of the estimated association. - Studies that have been conducted more than once have better statistical validity. - Studies with larger samples have wider confidence intervals.

True Statement(s) - A study that finds a 55% difference between groups demonstrates a stronger association than a study that finds a 10% difference between groups. - Confidence intervals reflect the precision of the estimated association. - Studies that have been conducted more than once have better statistical validity. False Statement(s) - Studies with larger samples have wider confidence intervals.

Jorge spots the newspaper headline "Eating pizza makes you angry." Reading the article carefully, Jorge finds that the researchers asked participants how many slices of pizza they consumed in the previous week, as well as how angry they felt in the previous week. Identify the true and false statements about the study and the news article

True: study describe in the article supports an association claim False: headline is reporting an association claim; headline change "eating pizza may lead to anger";# of pizza slices consumed was manipulated

Phuong is conducting an experiment on proofreading. He asks all participants to read a passage with several typos and to correct the errors. He asks one group to proofread by reading silently, a second group to proofread by reading aloud, and a third group to proofread by reading the passage both silently and backward. Phuong then calculates the average number of errors found by each group. He finds that the group that read silently and the group that read aloud found more errors than the group that read both silently and backward. Identify each element of this study as either a variable or a level of a variable. method of proofreading number of errors found proofreading by reading aloud proofreading by reading silently

Variable(s) method of proofreading number of errors found Level(s) of a Variable proofreading by reading aloud proofreading by reading silently

While reading news online, Johan comes across the headline "When stress is increased, men rush ahead, women more cautious." (The article is based on a study conducted by Lighthall et al., 2011.) In this study, researchers asked men and women to perform a decision task as many times as possible in a set period, in either a stressed or an unstressed condition. In the unstressed condition, men and women performed similarly. However, in the stressed condition, the number of decision tasks that men performed increased, while the number that women performed decreased. Identify each element of this study as either a variable or a constant.

Variable: # of decision tasks performed, amount stress Constant: type of decision task, length of the set period

Former NFL player at higher risk for brain, mood problems

association claim

People who run on a treadmill are less likely to be stressed.

association claim

Pet ownership is tied to greater well-being.

association claim

social media users less likely to be in relationships

association claim

thoughtful gift makes the gift giver feel closer to the recipient; drinking eight cups of water a day may boost energy levels; ice applied to twisted ankle prevents swelling

causal Claims

Nurturing parents lower the risk of depression in kids

causal claim

sleep problem may worsen ADHD symptoms

causal claim

In this example, JoAnn is sacrificing ____ validity to strengthen _____. JoAnn is interested in the availability of mental health care for emergency room patients. She has a limited amount of time with each participant, as patients are rapidly moved in and out of the emergency room. She decides to use a shorter, less reliable measure of mental health care availability in favor of getting as many participants as possible, enabling her to reach people of many different backgrounds, illnesses, and injuries

construct, external

The measured variable in an experiment is called the _____________, and the manipulated variable in an experiment is called the ________________.

dependent and independent variable

What are the following terms 'needs to demonstrate or 'does not need to demonstrate'? association between exercise and stress no stressed people who exercise

does not need to demonstrate'

A recent newspaper headline stated that 1 in 4 teens in the United States is concerned about climate change. You read the article and find that a study randomly surveyed a sample of teens from the Midwest via phone, and the researchers operationalized concern for climate change as "feeling afraid, angry, or guilty about climate change." What type of validity may be insufficient in this study?

external validity

To test a causal claim, scientist will often sacrifice ________ validity in exchange for maximizing ______ validity.

external, internal

1/3 of college students prefer taking notes by hand

frequency claim

53% of Americans say that the Internet has been essential during the COVID-19 pandemic

frequency claim

Most students prefer in person classes

frequency claim

you gotta have friends? most have just two true pals.

frequency claim

Solveig is testing whether a new experimental drug she designed can improve immune functioning. She recruits participants for a clinical trial and randomly assigns them to either a treatment group, in which they receive the drug, or a control group, in which they receive a placebo. After several weeks, she measures the differences between the two groups' immune functioning via blood test. Solveig announces that the treatment group had better immune functioning after the trial and claims that her drug was effective. Though the immune functioning between the two groups was different, that difference was not statistically significant. Assuming that Solveig's drug is effective, which type of validity might be insufficient in this study?

statistical

time of day, % of positive-emotion words, days of the week are what?

variable (s)