RESEARCH & STATISTICS

o What are the 3 types of psychological research?

o Experimentalo Descriptiveo Correlational

o The tendency to believe, after learning the outcome, that we knew it was going to happen is called…

o Hindsight Bias

o What is the only type of research that can show cause and effect?

o Experiments!

o In an experiment, the research must make a prediction trying to show a relationship between 2 variables. What is this testable prediction called?

o Hypothesis

o Researchers want their research to measure what it is meant to (it’s accurate). If it does, the research

is .

o Valid

o Research is considered reliable when it can be .

o Replicated (recreating the study & get the same results)

o Whatever is being manipulated in an experiment is called the

and what is being measured is called the .

o If , then

Independent Dependent

o Anything that causes change in the results of the experiment are called

.

o Confounding/extraneous variables

o In our experiment, the hypothesis was that Eating Cookies before the test would increase test scores. Name the independent, dependent, and 3 confounding variables.

o Independent: the cookieo Dependent: the test scoreso Confounding: weekend to study,

were told the answers, Ms. Williams is awesome…

o When choosing participants for an experiment, they should be placed into 2 groups. Name each group and which receives the independent variable.

o Experimental, Controlo Experimental receives the

independent variable

o What is often given to the control group to make them think they are in the experimental group?

o Placebo-receive NONE of the independent variable

o Ex: drug experiment, placebo is a sugar pill

o What is the purpose of having a random sample?

o It is representative of the population because each person has an equal chance of being included in the research

o To minimize differences between the control and experimental groups are as much as possible, participants should be placed into groups using

.

o Random Assignment

o What is the procedure called when neither the researcher nor the participants know who is in the experimental group?

o Double Blind

o In what type of descriptive research would you get a full, detailed picture of one person or small group?

o Case Study

o Name the biggest weakness of case studies.

o The findings are not always GENERALIZABLE to the entire population

o Name one positive and one negative about surveys.

o Positive: cheap & easy way to collect data

o Negatives: surveys are not always worded well, people are not always truthful, low response rate (maybe only 1 in 100 will respond)

o Name 2 important facts concerning a naturalistic observation.

o Do not intervene in any wayo Observe people in their natural

environmento Cannot know what people are

thinking/feeling because you are only observing their behavior

o What is the purpose of correlational research?

o To explore the relationship between 2 variables

o What are the 3 measures of central tendency AND explain each?

o Mean-averageo Median-value in the middleo Mode-value that occurs most often

o Given these values, find the mean, median, and mode.

o 10, 10, 8, 6, 1

o Mean: 7o Median: 8o Mode: 10

o What measure of central tendency is most affected by oultiers?

o Mean

o What is the number that shows the strength of a relationship between 2 variables?

o Correlation coefficient

o Which of the following has a stronger correlation?

o +.03o -.87o +.80o -.34

o -.87o Remember the closer to +1 or -1 the

stronger the relationshipo The closer to 0 the weaker the

relationship

o What is the range of the following values?

o 17, 45, 15, 26, 38

o 30o Remember, highest score-lowest

score=range

o A correlation is STATISTICALLY SIGNIFICANT if the chances of it occurring by chance are less than

%?

o 5%

o Look at the following scatterplot. What type of relationship do you see?

o Positive Correlation, both values are increasing

o A negative correlation if one value is increasing and one is decreasing

o If participants in an experiment know that they are being studied, it could alter the results. What is this phenomenon called?

o Hawthorne Effect

o What is the average distance from the mean called?

o Standard Deviation

o In a normal distribution of scores, what percentage of the scores will fall within 1 standard deviation?

o 68%o 95% within 2 SDso 98% within 3 SDs

o What is it called when we think that a relationship exists when it really doesn’t?

o Illusory Correlation

o You are responsible for knowing the following:

o SQ3Ro Longitudinal studieso Cross-sectional studieso Ethics