exam 3

Question 1

frequency distributions

Answer 1

a summary of the number of cases in categories

• frequency distribution tables
• frequency distribution graphs/charts
  
  • histograms (connected)
  • polygons
  • bar graphs (no correct order)

Question 2

measures of central tendency

Answer 2

-mean: average
-median: score in the middle
-mode: score that occurs the most often
note 1: mean=median=mode in normal distributions
note 2: mean and median only make sense in nominal distributions

Question 3

descriptive statistics

Answer 3

findings that help us organize, summarize, and simplify results

Question 4

inferential statistics

Answer 4

findings that help us make generalizations about the population
helps us find the parameter, summary values that describe a population

Question 5

measures of variabilty

Answer 5

the spread of individual scores

• variability: the spread of scores in a distribution
• standard deviation: a standardized measure of the variance of the sample

Question 6

problems with statistics

Answer 6

statistics are almost never a perfect representation of our parameters, they contain sampling errors
sampling errors- naturally occurring differences between sample statistics and the corresponding population parameter (the average of the groups is not the same as the population)

Question 7

hypothesis test

Answer 7

a statistical test used to evaluate the credibility of an effect in the population

Question 8

null hypothesis

Answer 8

a statement about the population that you would like to disprove (e.g. there is no difference or relationship between group a and b)

Question 9

test statistics

Answer 9

mathematical value that measures the degree to which the sample data are in accord with the null hypothesis

Question 10

p-value

Answer 10

the probability that the results obtained are merely due to chance

Question 11

alpha

Answer 11

the cutoff percentage used to compare to p in order to determine if our test statistics is “significant”

Question 12

statistical significance

Answer 12

the probability that the effects obtained are due to chance

Question 13

effect size

Answer 13

the projected magnitude or strength of the effect

Question 14

APA’s Human Subjects Guideline

Answer 14

• no harm (during and after)
• privacy and confidentiality
• institutional approval
• competence (of researchers and analyzers)
• record keeping
• informed consent to research
• reasonable inducements (incentives)
• limit of deception
• debriefing

Question 15

informed consent information

Answer 15

• purpose
• right to decline participation before, during, or after
• foreseeable consequences and benefits
• alternative options
• confidentiality and its limits
• contact information

Question 16

apa guidelines for animal research

Answer 16

• proper acquisition, care, and disposal of animals
• proper training for all involved on the care needed and experimentation methods
• minimal discomfort, pain, illness, and infection of animals
• quick death
• anesthesia for surgery

Question 17

institutional review board

Answer 17

committee responsible for reviewing research plans and setting protocol in order to ensure safety of research subjects

Question 18

comparing two groups

Answer 18

t-test

Question 19

comparing more than two groups

Answer 19

anovas

Question 20

critical values

Answer 20

the test statistic that is the cutoff for rejecting the null hypothesis

Question 21

goodness of fit

Answer 21

is it what we expected?

Question 22

test of independence

Answer 22

is the major distribution the same?

Question 23

IRB (Institutional Review Board)

Answer 23

committee responsible for reviewing research plans and setting protocol in order to ensure safety of research subjects

Question 24

comparing two groups of individuals

Answer 24

z-test