research methods EXAM 3
Ravi records his observations of a patient suffering from binge eating disorder. He does this for a period of 12 months, and now he has a thorough analysis of the behaviors and patterns associated with the patient's binge eating disorder. This is an example of a
case study
Andrea is told that the means of two groups in a study were statistically significant. She knows the means and standard deviations of the two groups and is interested in calculating an estimate of effect size. Given this information, which effect size estimate should she calculate?
cohen's d
variables that have inherent ordering ex/ from low to high on some quality; rankings
continuous variables
range
difference between highest and lowest score
sampling error
difference between sample statistics and population parameters
Dr. Afzal finds that students who work less than 10 hours a week have significantly higher test scores than students who work more than 10 hours a week. In order to determine the magnitude of the effect of work hours on test scores, he should calculate an estimate of the
effect size
A teacher displays her students' test grades on a notice board. According to the results, 7 students received the grade of A, 10 students received the grade of B, 18 students received the grade of C, 4 students received the grade of D, and 1 student received the grade of E. In statistical terms, this is a
frequency distribution
null hypothesis
given sample data, it is HIGHLY LIKELY (probable) that NO TRUE DIFFERENCE exists in population > any differences in sample means can be explained by (random) sampling error
alternative/research hypothesis
given sample data, it is HIGHLY UNLIKELY (improbable)that NO TRUE DIFFERENCE exists in population > differences in sample not explained by sampling error alone
When studying the effect of temperature on the sales of ice creams, a researcher records the number of ice creams sold on cold days and the number sold on hot days. In this scenario, the researcher will most likely compare ________ to describe the results.
group means
standard deviation
indicates the average deviation of scores from the mean
Arafa has collected data on the relationship between physical attractiveness and judgments of personality characteristics. In order to determine if the results obtained from the sample are representative of the population, Arafa will need to employ ________ statistics.
inferential
what is true about non-concealed observation?
it is preferred over concealed observation from an ethical standpoint
alpha level
level of probability set as a "cut off" for rejecting/retaining null hypothesis > p value less than .05 = reject > p value greater than .05 = retain / fail to reject null
nominal scale
measurement in which numbers are assigned to objects or classes of objects solely for the purpose of identification
A teacher displays the results of a test on a notice board. According to the results, half the students had scored more than 70% on the test. Which measure of central tendency does this scenario exemplify?
median
median
middle number in ORDERED set / average of 2 middle numbers
mode
most occurring number
what kind of observation might involve participating in a police ride along to examine daily activities of officers?
naturalistic observation
what type of observation is sometimes called field work / field observation?
naturalistic observation
Craig examines the effect of different genres of music, such as jazz, rock, and rap, on task performance. Which type of measurement scale do the genres of music represent?
nominal scale
what hypothesis Staes that the independent variable has no effect?
null
descriptive statistics
numbers used to SUMMARIZE & describe data > allows precise measurements to be made
negative correlation
one variable increases as the other decreases \
postive correlation
one variable increases as the other increases /
A professor at a university ranks subjects based on students' preferences identified through a survey. Science is ranked first, mathematics second, and management third. In this scenario, which of the following types of measurement scale has the professor employed?
ordinal scale
A researcher wants to gather information on citizens' reactions to the local government's decision to construct a new airport in their neighborhood. The researcher gathers groups of citizens and asks them to discuss the advantages and disadvantages of the proposed airport. This type of data gathering can be referred to as a(n) _________ approach to describing behavior.
qualitative
when the conclusions of research are based on the interpretations of the investigator, _________ research has likely been employed. If the conclusions are based upon statistical analysis of data, __________ research has likely been employed.
qualitative, quantitative
when testing the differences between means, the null hypothesis suggest that any observed difference is due to what?
random error
what scale of variables have both equal intervals and an absolute zero point that indicates the absence of the variable being measured?
ratio scale
Roberto bullies his younger brother in the absence of his parents. However, when his parents are around, he is very affectionate toward his brother. What kind of behavior does Roberto exemplify?
reactivity
According to her statistical analysis, an investigator found that significantly more men than women used punishment to discipline their children. Thus, the investigator would
reject null hypothesis
Daniela and Alicia are conducting a systematic observation study on children's aggressive behavior in playgrounds. Daniela concludes that boys display more aggressive behaviors than do girls, whereas Alicia concludes the opposite. Which methodological issue would be of most concern in this study?
reliability
when testing the difference between means, what hypothesis suggests that population means are not equal?
research
frequency distribution
summary of the frequency of individual values/ranges of values for a variable
in the context of statistical tests, significant results are most likely to be obtained when
the effect size is large
p value
the exact probability that the null is true, given sample data
how does the sample size affect determinations of the statistical significance?
the larger the sample size, the more accurate the estimation of the true population value
variance
the square of the standard devation
Tevy reports that individuals who follow her diet plan lose more weight than individuals who follow Jake's diet plan. In actuality, there is no difference in weight loss between those following Tevy's diet plan and those following Jake's diet plan. In this case, Tevy's claim illustrates a ________ error.
type one
measures of central tendency
use a single value to fine the "middle" of the distribution mean, median, mode
chi - squared independence
used when DV is CATEGORICAL tests whether there is an association between frequencies of different categories
independent samples t test
used when DV is CONTINUOUS tests whether 2 means differ from one another / if changes in IV cause changes in DV
one way anova
used when DV is CONTINUOUS + 2 MORE CONDITIONS tests whether there is a DIFFERENCE AMONG MEANS OF DIFFERENT CONDITIONS
factorial anova
used when DV is CONTINUOUS + there is MORE THAN ONE IV tests whether EACH FACTOR / INTERACTIONS BETWEEN FACTORS are associated w differences in mean
related measures t test
used when DV is continuous + MEASURED TWICE (pretest posttest) tests whether there is a CHANGE in means
inferential statistics
uses probability theory to understand what is happening in a population by using sample data > "did my finding occur by chance?"
categorical variables
variables that have no inherent ordering ex/ gender, nationality, types of sandwiches
measure of variability
when scores vary more around a mean, they have a large VARIANCE & STANDARD DEVIATION > both measure amount of "spread" of numbers around center
The grades received by 10 college students on a test are A, B, D, A, A, A, C, B, C, and A. From this data, it can be inferred that the mode is
A
which of the following is true regarding ratio scales? A they do not have equal intervals B they are best amplified by time, weight, height, and other physical measures C they exhibit minimal quantitative distinctions D they are typically used to measure personality traits
C they are best exemplified by times, weight, length, and other physical measures
A student is interested in the effect of environmental conditions on task performance. She makes participants complete a series of math problems under different conditions of temperature (cold, warm, and hot) and different noise conditions (quiet and noisy). The most appropriate test to analyze the data would be a
F test
type one error
INCORRECTLY REJECT null - when null is actually TRUE
type two error
INCORRECTLY RETAIN null hypothesis - when ALTERNATIVE is TRUE
ratio scale
a quantitative scale of measurement in which the numerals have equal intervals and the value of zero truly means "nothing"
interval scale
a scale of measurement in which the intervals between numbers on the scale are all equal in size
ordinal scale
a scale of measurement in which the measurement categories form a rank order along a continuum
before employing inferential statistics, Alberto selects the probability level required for statistical significance. This level is referred to as the ___________ of the test.
alpha level
the research approach in which the research does not actually collect original data but analyzes existing data is called what?
archival research
mean
average of all scores
