psych 105 midterm 1

Empiricism

The belief that accurate knowledge can be acquired through observation. locke

The Scientific Method

a set of principles about the appropriate relationship between ideas and evidence

theory

hypothetical explanation of a natural phenomenon

what are the 3 things that make studying people difficult

• complexity

• variability

• reactivity

validity

the extent to which a measurement and a property are conceptually related

reliability

tendancy for a measure to produce the same measurement whenever it is used to measure the same thing

demand characteristics

aspects of an observational setting that cause people to behave as they think they should

what are methods used to reduce demand characteristics?

• cover stories- decpetion and debreifing

• the unrelated-experiments technique-start with one experiment and then conduct another

• use of nonreactive measures- ex cortisol levels

Naturalistic observation:

A technique for gathering

scientific information by unobtrusively observing people in

their natural environments

information used in naturalsitic observation may be…

▫ Measured as it occurs

▫ Already recorded by others

▫ Recorded on videotape to be coded later

what is ecological validity?

how study results apply to real life situations

observer bias

researchers see what they want to see- their observations match their predictions which poses a threat to the validity of research

what did the rosenthal and fode study show

had one maze for smart rats and one maze for dumb rats. the rats where actually the same but showed different results due to the difference in treatment they got. showed observer bias

double blind study

An observation whose true purpose is hidden from both the observer and the person being observed

frequency distribution

A graphical representation of measurements arranged by the number of times each measurement was made.

descriptions

graphic representations and statistics

what are three neasures of central tendancy

mode, median, and mean

what is mean?

average- add all values then divide by number of values

what is mode?

number that occurs most often in a data set

what is median?

middle number, if odd pick the number in the middle, if even add the 2 middle numbers and divide by 2

what is discriptive research?

describe behavior in natural settings- case studies, naturalistic observation, surveys

what is a correlational study?

explores the relationship between 2 or more variables- but there is no manipulation

what are experimental studies?

investigate a cause and effect relationship

-manipulation

what is random assignment

participants placed into groups by chance, to contol systematic impacts of self selection

if variables cannot be manipukated due to ethical constraints what needs to be done?

a correlational or descriptive study

what is a case study?

in depth analysis of individuals groups or events.

what did dr. deb roy investigate?

how humans specifically infants learn language through intensive observation of single individuals

what are the advantages for using case studies for research?

• useful for rare phenomenon

• may challenge validity of theories

• can illustrate effectiveness of programs for special populations like failure to thrive infants

what are the disadvantages for using case studies for research?

• poor method of determining cause and effect relations

• genealizability questionable

• researcher bias

what allows neuroscientists to study localization of brain function

brain imaging techniques

which way does the dorsal stream go?

from occipital towards parietal- used for coordination and movement

which was does the ventral stream go?

from occipital towards temporal- used for object recognition

what i naturalistic observation?

observation of behabior in a natural setting

what are the advantages of naturalistic observation?

provides a rich description of behavior

what are the diadvantages of naturalistic observation?

does not permit clear causal conclusions

why do researchers need a proper representative sample of a population?

because they cannot study the entire population the sample must reflect important characyeristics of the whole population- use random sampling

what are the major drawbacks of surveys?

• unrepresentative samples can lead to faulty generalizations

• surveys rely on participants self reports which relies on honesty of participants

• data cannot be used to draw conclusions about cause and effect

what are the benefits of surveys

• convienient

• cost effective'

• anonymity encourages people to participate and be honest

what is a bimodal distribution?

has 2 modes/ separate areas of peak frequencies- unlike normal distribution which is unimodal

normal distribution

the mean is = to the median

where will the mean be on positively skewed?

higher than the median

where will the mean be on negatively skewed?

lower than the median

standard deviation?

discribes the average difference between the measurements in a frequency distribution and the mean of that distribution

standardized score?

expressed in the number of standard deviations that the orginal score is from the mean

matched samples?

technique where participants in two groups are identical in terms of a third variable

matched pairs?

each participant is identical to one other partipant in the terms of a third variable

descriptive studies?

describe behavior systematically without investigating relationships between specific variables

within subject experiments?

each subject participates in each part of the study- can face fatigue or practice but have greater statistical power

what are between subject experiments?

each control/group has different participants

 

 

Psychology

scientific study of behavior and mental processes

behavior

the responses or actions that we can observe directl

mind

internal processes and states that cannot be observed directly but are instead inferred from measurable responses

science

a process of gathering and evaluating empirical evidence systematically in order to answer research question

inferential statistics?

procedures for calculating the probability that the observed results could derive from chance alone

error?

reduces the chance of finding statistcially significant results

bias?

can lead to the false conclusion that a hypothesis has been supported when in fact some irrelevant factor has caused the result

when does a sampling bias occur?

when the sample is not actually representative of the population because the probability with which members of the population have been selected for participation is not known

internal validity?

the extent to which we can trust the conclusions that have been drawn about the causal relationship between the independant and dependant variable

external validity?

the extent which results can be generalized beyond specific settings and participants uced in the experiment to other places people and times

why was the milgram study not ethical?

Milgram Study (1974): The study tested obedience to authority by having participants (“teachers”) administer fake electric shocks to a “learner” (confederate) when they answered questions incorrectly. Despite hearing the learner’s protests, many continued when instructed by the experimenter. The study showed that ordinary people are likely to obey authority even when it causes harm, but it was unethical due to deception, stress, and limited ability to withdraw.

what are the general guidlines and principles of research?

-respect for human dignity

-repsect for free and informed consent/ freedom to make decisions

-minimize harm

-maximize benefit: benefit society as a whole

-respect for vulnerable persons

-respect for privacy and confidenntiality

variance?

a statistic that represents the sum of the squares divuded by the sample size, how much values differ from the mean

histograms?

graphically represent the frequency of particular groups of scores

what do box plots show?

important information about the distribution of scores

• median- line at center of box

• variability- shown by outliers and whiskers

• aymmetry: shown by differences above and below

• outliers: scores that are extremely high or low

what is error variance?

variance from factors that were not controlled in an experiment- like boredom, distraction, measurement error

r2?

R² (R-squared) is a statistic that tells you how much of the variation in one variable is explained by another variable in a regression or correlation context.

what does it mean by t-tests are parametric?

the population needs to be normally distributed to use this test

what is the purpose of a t-test?

to test if two means are statistically significant from eachoter

what does it mean if two frequency distributions have lots of over lap

high variability

what does it mean when frequency distributions have little overlap?

little variability- and higher chance of being statistically significant

what is the T stat?

The T value in a t-test tells you how big the difference between two group means is relative to the variability of the groups.

• Bigger T → the groups are more different compared to the spread of scores

• Smaller T → the groups are closer together compared to the spread of scores

In other words:

The T-statistic measures the signal (mean difference) relative to the noise (variability in the data).

what makes a T stat higher?

T gets higher when:

• The difference between group means is larger

• The variability (spread) within groups is smaller

• The sample size is bigger (because larger samples reduce error)

what makes a t stat smaller?

Low T → small difference / high variability → less likely significant

single sample- t-tests?

-randomly distributed

-normal selection

-used to know if difference betweeb the sample mean and the known population is significant

-A single-sample t-test is a type of t-test used to compare the mean of one group to a known or hypothesized value (instead of comparing two groups).

related samples t-test?

-two samples are compared with eachother

-particpants in one group have something in common with the participants in the oher

-same people can be tested under both conditions

independant samples t-test?

two samples are compared, participants have nothing to do with eachother, random assignment to conditions

what type of formula are t-tests calculated with

a ratio formula- differance betweeb two means/variability=signal/noise

Ho

null hypotheisis

Ha

alternate hypothesis

effect size?

how much effect one variable has on another

what are powerful tests?

tests that detect large effects- large differences between null and alternative

-researchers should specify minimum difference that is worth their attention and design studies with that effect size in mind

critical period:

period in childhood when exerience and language produces optimun language acquisition

babies in utero may respond to their mother speech through what?

kicking/movement

what do new borns prefer over strangers?

their mother voices

can newborns percive speech?

yes they can, they prefer their mother voice

what are the steps to speech?

1. newborns and young babies: make sounds like cry sneeze

2. 2 months: infants begin to produce vowel like sounds

3. 6 months: cooing develops into babbling- speech like sound

4. 10-12 months: use single words

what is infant-directed speech/motherese?

thought to attract and maintain the attention of infants

higher in pitchs, more variable in pitch, more exaggerated in intonation, slower in pace, provides more language cues

what are phonemes?

basic building blocks of language- linked together to create words- consist if consonant and vowel sounds

when can infants distinguish phoneme sounds?

as early as 1 month after birth

what are morphemes?

smallest meaninful units of language

• words, prefizes, suffixes that are used in consistent ways to modify words

what is deep structure?

meaning of a sentance

what is surface structure?

the way a sentance is worded

what are the three theories of vocabulary spurt?

1. naming insight- all things have words/all words refer to things

2. change in concepts-more words are used when concepts become more detailed and differentiated

3. ability to sort objects-marks acceleration in word learning

what is fast mapping?

connecting new words with their refferents so quickly that they cant be considering all of the possible meanings for the new words

what is joint attention

learning is more likely to take place when adults look at the object or action while saying its name

what is a holophrase?

one word utterance by a child to communicate more than the typical meaning of that word

what are naming errors?

underextension: defining a word to narrow

overextension: defining a word too broad

dissapearance of these is gradual as childs language and understanding becomes more accurate

stages of early grammar development?

1. 2 years: multiword utterances are produced

2. 2-5 years: progress in grammer

what is basic child grammar?

the grammatical properties of early childhood language, that are found in many languages and thought to universal

telegraphic speech?

Telegraphic speech is a stage in language development when a child speaks in short, simple sentences that mostly include content words (nouns, verbs) and omit smaller grammatical words (like articles, prepositions, or auxiliary verbs). like want cookie instead of i want a cookie