Kap 2; Thinking Critically with Psychological Science

Question 1

How does our everyday thinking sometimes lead us to wrong concnlusions? 3x

Answer 1

Hindsight bias - belief that after learning an outcome that we could have foreseen it.

Overconfidence - tendency to be more confident than correct

Our eagerness to percieve patterns in random events

= overestimation of comman sense thinking

Answer is - testable questions can be addressed by the scientific method to overcome such biases and shortcomings

Question 2

How do theories advance psychological science?

Answer 2

By testing their hypotheses, researchers can confirm, reject or revise their theories.

Operational Definition is important for it to be replicated by others. If successful replication, confidence in the conclusion will be greater.

Question 3

How do pschologists use case studies, naturalistic observations and surveys to observe and describe behaviour?

and why is random sampling important?

Descriptive is/is not

generalization, representative sample/random sample

Answer 3

Descritive methods - case studies, naturalistic observation, surveys - show us what can happen and they may offer ideas for further study but they do not explain behaviour. Not a cause and effect because researchers cannot control variables.

The best basis for generalization about a population is a representative sample, in a random sample, every person in the entire population being studied has an equal chance of participating.

Question 4

What does it mean when we say two things are correlated

and what are positive and negative correlations?

Answer 4

Correlation - Two variables are correlated. How well one predicts the other.

Postive correlation : ++ / –

Negative correlation : +- /-+

Strength of correlation = Correlation coefficient (r)

+1.00 (a perfect positive correlation)

-1.00 (a perfect negative correlation)

0 (no correlation)

The relationship may be displayed in a scatterplot, in which each dot represents a value for the two variables.

Question 5

What are illusory correlations,

and what is regression towards the mean?

Answer 5

illusory correlations - random events that we notice and falsely assume are related (our eagerness to see patterns)

Regression towards the mean - the tendency for extreme or unusual scores to fall back (regress) toward their average.

ex: presterar ovanligt bra andra halvlek, eller på jobbet en dag. Lätt att bli besviken…

Question 6

Why do correlations enable prediction but not cause-effect explanation?

Answer 6

Correlations enable predictions because they show how two factors are related. A correlation can indicate the possibility of a cause-effect relationship.

Question 7

What are the characteristics of experimentation that make it possible to isolate cause and effect?

• Manipulation
• Random Assignment
• Independent variable
• Dependent variable
• Double-blind procedure

Answer 7

Conduct experiments, manipulating one or more variables of interest and controlling other variables.

Random assignment - minimizes confounding variables, such as preexisting differences between the experimental group and control group.

Independent variable - the variable manipulated

Dependent variable - the variable measured

Double-blind procedure - avoiding placebo effect and researcher bias

Question 8

How would you know which research design to use?

Answer 8

We want meaningful results.

First researchers genreate testable questions and then consider the best research design to use in studying those questions.

(experimental, correlational, case study, naturalistic observation, twin study, longitudinal or cross-sectional)

Next psychologists measure the variables,

then interpret their results, keeping possible confounding variables in mind

Question 9

How can simplified laboratory conditions illuminate everyday life?

Answer 9

It is the general principles - not the specific findings - that help explain everyday behaviours.

In that way a controlled, artifical environment is not of importance.

Question 10

Why do psychologist study animals, and what ethical guidelines safeguard human and animal research participants?

How do psychologists’ values influence psychology?

Answer 10

Vissa är enbart intresserade av djurs beteende, andra vill förstå den fysiologiska och psykologiska processen som vi delar arter sinsemellan.

APA - etiska riktlinjer för att skydda människan

(informed consent, debriefing)

Ens personliga värderingar som psykolog påverkar val av forskningstema, deras teorier och observationer och deras professionella råd.

Den mesta av psykologins forskning används för att tjäna mänskligheten.

Question 11

How do we describe data using three measures of central tendency,

and what is the relative usefulness of the two measures of variation?

Answer 11

Descriptive Statistics

1. mode (den mest frekventa scoren)
2. mean (medelvärdet)
3. median (middles score in a group of data)
   * Measures of central tendency* neatly summarizes data; Measures of variation tell us how diverse data are.
4. Range (gap between highest and lowest scores)
5. Standard Deviation (how much scores vary around the mean)

Scores often form a normal curve.

Question 12

How do we know whether an observed difference can be generalized to other populations?

Inferential statistics

Internal validity

Representative sample, variabilitet

Statistisk signifikant

Answer 12

Forskare använder sig av inferential statistics (sätt att bestämma trovärdighet och signifikans av en observerad skillnad bland resultaten för olika grupper)

Internal Validity

Representative sample med låg variabilitet och som består av många fall.

Vi kan säga att en observerad skillnad är statistisk signifikant om sample average är trovärdig.