4700 Final
When are descriptive measures most often used?
To describe how often something occurs
How are inferential statistics most often used?
To make inferences from the sample to the population
The major difference between an experimental and an observational study is that an experimental study can determine cause and effect, whereas an observational study cannot
True
True or False, If a measurement is valid, its scores will be reliable.
True
True or false, a test can be reliable, but not valid.
True
An in-depth analysis of a unique condition or situation to reach a greater understanding about other similar situations is known as a _________________.
case study
Retrospective; starts with an end point and work backward, figuring out what might have caused that outcome:
case-control study
As a result of the brain's attempt to simply information processing, ________________ are predispositions towards certain kinds of thinking that occurs when people are rapidly processing and interpreting information
cognitive baises
Identify which kind of observational study design is being described: Longitudinal/Prospective; tracks the same groups of people over an extended period of time:
cohort study
__________________________ is a type of statistical validity in which a proposed test is compared to a criterion standard within a close period of time to establish its accuracy
concurrent
_______________ is the extent to how well a test measures a theoretical attribute that has no definitive criterion, is difficult to measure, or cannot be directly observed.
construct validity
A group of subjects that is similar to the experimental group except that they do not receive the experimental treatment is known as the _________________________.
control group
Measures of ____________________________ are established when the results of one test are compared with the results obtained when using an accepted standard or criterion.
criterion-based validity
Snapshot; Assesses information about a population at one point in time:
cross sectional survey
Your current exam mean is 93.2. If you receive a 87 on the next exam, this will have the effect of:
decreasing your mean
Creating specific examples from generalized statements is an example of what?
deductive reasoning
When measuring the effects of water consumption on a runner's performance, speed and distance are examples of ______.
dependent variables.
___________ statistics involve collecting, organizing, and summarizing data.
descriptive
Which of the following would be used to describe the type of statistical methods used to organize and describe the characteristics of a collection of data?
descriptive statistics
A _________________________ study occurs when both subject and researcher do not know who receives a given treatment.
double blind
In a meta-analysis, the results of various studies on a topic are quantified using a standard measure that is called the _________________
effect size
_________________________ is the study of the distribution and determinants of disease and health conditions and the subsequent application to control health problems.
epidemiology
The conscientious, explicit and judicious use of best current evidence indecision making is known as what?
evidence-based practice
n a research study in which the treatment involved quite intense physical training, 40% of the participants in the treatment group dropped out as compared with 5% of the control group. This threat to internal validity is called
experimental mortality
_______________ validity is the weakest type of validity because all that can be said is that it appears to be obvious that the test or device is measuring what it is supposed to measure.
face
The less precise levels of measurement contain all the qualities of the scales above them.
false
The most accurate & definitive measure of a variable is sometimes referred to as a __________________
gold standard
Which threat to internal validity is introduced when the researcher has some expectation about the performance of a subject and is also involved in assessing the subject, possibly biasing the researcher's judgment?
halo effect
The major limitation of observational studies is
inability to experimentally establish cause and effect
The major weakness of epidemiologic studies is
inability to experimentally establish cause and effect
In epidemiology/biostatistics, the ___________________________ is the rate at which NEW cases occur in a population during a specified time period.
incidence rate
Your current exam mean is 97.2. If you receive a 99 on the next exam, this will have the effect of:
increasing your mean
As you change what happens to the __________, you will observe what happens to the __________.
independent variable, dependent variable
Creating generalized statements from specific examples is an example of what?
inductive reasoning
_______ statistics are often (but not always) the next step after you have some basic understanding of data.
inferential
What type of statistics employs the use of sample data that is used to infer information about the population?
inferential statistics
__________________________ is a measure of reliability used to determine the consistency of scores obtained by 2 or more different test administrators, illustrating uniformity among the data collection procedures.
inter-rater reliability
The degree to which a study establishes the cause-and-effect relationship between the treatment and the observed outcome is known as ______________
internal validity
Inferential statistics involve _________ the data.
interpreting
Inferential statistics is most often used for which of the following?
interpreting data
Which of the following is NOT a use of descriptive statistics?
interpreting data
If the underlying continuum we are measuring assumed equal intervals, at what level of measurement is the associated variable being measured?
interval
This is the level of measurement where outcomes are based on some underlying continuum where it is possible to speak about how much more a higher performance is than a lower one:
interval
___________________________ is a measure of the day to day consistency of the same test administrator, illustrating the consistency of data collection procedures.
intra-rater reliability
______________ are errors or flaws in reasoning when deceptive, invalid or otherwise faulty reasoning are used in the construction of an argument.
logical fallacies
The descriptive statistic that is also referred to as the "average" is the:
mean
This measure of central tendency can be considered the most precise:
mean
Variability is a measure of how much individual scores differ from the ______________.
mean
What would be your preferred measure of central tendency if you had the following data: $31,550; $33,750; $34,700; $37,550; $39,275?
mean
Which measure of central tendency is most influenced by outliers?
mean
Which of the following is not a measure of variability?
mean
This consists of the middle point of a set of values
median
This measure of central tendency can be considered the least precise:
median
What would be your preferred measure of central tendency if you had the following data: $32,400; $42,500; $47,250; $49,570; $145,850?
median
Which measure of central tendency is also known as the midpoint for a set of scores?
median
The type of descriptive statistic that tells you the most popular/most frequent choice from a number of choices is the:
mode
What would be your preferred measure of central tendency if you had the following data: 57 males and 23 females?
mode
When describing a set of nominal data, a researcher should use which of the following measures of central tendency?
mode
Moving from the nominal to the ratio levels of measurement, your data become...
more precise and detailed
Which of the following best describes the Mode?
most frequently occurring values
This threat to external validity occurs when a research introduces more than one experimental variable, risking the treatments inhibiting or enhancing each other.
multiple treatment interference
Which of the following symbols represents sample size?
n
A distribution of scores in which almost the entire class scored very high, but a few students scored fairly low, would be:
negatively skewed
A double-blind experiment is one in which
neither the researcher nor the participants know which participants receive the experimental treatment
This is the least precise level of measurement.
nominal
This is the level of measurement where outcomes can only be placed into unranked categories.
nominal
Which level of measurement is concerned only with the characteristics of an outcome that fits into a category?
nominal
National Heart, Lung, and Blood Institute's evidence category C includes evidence from ______.
non-randomized trials, observational studies.
_________________ refers to the consistency of the test administrator during data collection.
objectivity
When a measurement is made on a subject, the result is called an _________________, which is a combination of the true score that represents the subject's real score, and the error score, due to any mistake in data collection.
observed score
If you are interested in describing the order of variables along a continuum, what level of measurement would you use?
ordinal
In a local road race, Moe finishes in third place. This number is an example from a (an) _____________ scale.
ordinal
This is the level of measurement where outcomes can be rank ordered.
ordinal
National Heart, Lung, and Blood Institute's evidence category D includes evidence from ______.
panel consensus judgment.
Prevalence of disease differs from incidence of disease in that prevalence refers to the number of
people who presently have a disease, whereas incidence relates to new cases
When a control group receives a false treatment while the experimental group receives the real treatment, the control group has been given a _______________.
placebo
What is the larger group from which a sample is drawn?
population
What does the large N represent?
population size
A distribution of scores in which almost the entire class scored very low, but a few students scored fairly high, would be:
positively skewed
______________________________ is the extent to which a score on a scale or test predicts scores on some criterion measure.
predictive validity
In epidemiology/biostatistics, _______________________________ is the proportion of people in a population who have a condition/attribute at a specified time.
prevalence rate
In the following example, what is the independent variable? Does protein intake improve biceps circumference in male weight lifters?
protein intake
The chance placement of subjects into groups so that the groups do not differ at the beginning of the experiment is known as ____________________________.
randomization
The gold standard for research in the health sciences is
randomized control trial
The gold standard for research in the health sciences is the
randomized control trial
National Heart, Lung, and Blood Institute's evidence category B includes evidence from ______.
randomized controlled trials with a limited body of data.
National Heart, Lung, and Blood Institute's evidence category A includes evidence from ______.
randomized controlled trials with a rich body of data.
If you subtract the smallest number in the distribution from the largest, what type of variability is being calculated?
range
Which measure of variability is most general, and hence least useful?
range
Which measure of variability should never be used alone to reach conclusions regarding the variance of a distribution?
range
Only this level of measurement has a true zero.
ratio
This is the level of measurement where outcomes are based on some underlying continuum that also contains a true or absolute zero.
ratio
This is the most precise level of measurement.
ratio
Which of the following levels of measurement provides the most information about a variable?
ratio
This threat to external validity is concerned with when pre-testing subjects, it may alter their perception of the experimental treatment and motivate them to perform better than if they had not been exposed to the pre-test.
reactive effects of pre-testing
_________________ is the likelihood of an event occurring in a group of people when compared to another group of people
relative risk
____________ is a measure of the degree of consistency or repeatability of a test.
reliability
The dependent variable
represents the response or outcome from the manipulation of the independent variable the variable that is observed or measured in the research process is the one that is expected to change as a result of the treatment
A researcher predicts that there will be a positive relationship between attitude scores and grade point average. This is an example of a
research hypothesis
________ is to smaller group of data as population is to larger group of data.
sample
What does the small n represent?
sample size
A pretest of knowledge about microcomputers is given to a group of students 5 min prior to a film on the subject. A posttest given 10 min after the film showed a 10-point gain from the pretest. The researcher concludes that the film produced the gain. Which of the following is likely the threat to internal validity?
testing
In an experiment
the independent variable is manipulated by the researcher to see whateffect it has on the dependent variable
Unless you have sufficient evidence otherwise, you must assume that...
the null hypothesis is true
When a researcher states that a result is significant, this means that
the result is unlikely to be a chance occurrence
When a hypothesis is repeatedly supported by multiple investigations and laboratories, it can become a ______.
theory.
Which of the following is true of z scores that fall below the mean?
they are negative
Which of the following is true of z scores that fall above the mean?
they are positive
Statistics describes a set of __________ that is used for describing, organizing, and interpreting information.
tools and techniques
A population can be considered all of the occurrences with certain characteristics.
true
A standard deviation equal to 0 indicates no variance in your data
true
All members of a sample are members of the population.
true
The standard deviation is sensitive to extreme scores.
true
When a researcher predicts that there will be a difference between 2 groups but is unable to predict which group will score higher than the other, the researcher is using what kind of hypothesis?
two-tailed
When you reject the null hypothesis when there is actually no difference between groups or relationships between variables, you are making a:
type 1 error
Which of the following occurs when you reject the null hypothesis when it is really true?
type 1 error
Which of the following occurs when you accept the null hypothesis when it is really false?
type 2 error
The extent to which an instrument measures what it is intended to measure is known as
validity
Which of the following measures how scores differ from each other?
variability
What is obtained by squaring the standard deviation?
variance
In a study designed to assess the comparative effectiveness of two workbooks used in teaching students about laboratory procedures, the independent variable of the study would be
workbooks
What is the symbol used to represent the mean?
x with a bar over it
Which of the following occurs when you accept the null hypothesis when it is really true?
you have made the correct decision
The entire normal curve contains this percentage of scores:
100%
What percent of all scores fall above a z score of +1?
16%
Which of the following sets of data illustrates skew?
23, 37, 42, 51, 147
What is the range for the following set of scores: 34, 14, 17, 57, 22?
43
If a researcher sets the decision rule p value at .05, what is the probability of making a Type I error?
5%
Which of the following sets of scores has the least variability?
5, 4, 5, 6, 5
Under the normal curve, approximately what percent of scores fall between and -1 to +1 standard deviations around the mean?
68%
Which of the following sets of scores has the greatest variability?
7, 10, 11, 15, 19
What percent of all scores fall below a z score of +1?
84%
This percentage of scores fall within three standard deviations of the mean:
99%
True or False? An observational study design has less potential for bias than a randomized controlled trial (RCT).
False Because the investigator does not control the level of exposure to the independent variable, an observational study design is more prone to error than an RCT.
External validity is the:
Generalizability of a study
The _____________________ refers to the threat to internal validity when a researcher has some expectation about the performance of a subject.
Halo Effect
Just before the posttest, students in the control group were shown a film in another class that related directly to the subject matter being studied in the treatment group. This represents what kind of threat to internal validity?
History
A survey authorized by the CDC to assess daily physical activity and nutritional habits in American children is an example of what type of evidence?
Observational research
What are the three tools used to assess variability?
Range, Standard Deviation, and Variance
_______________________ is the threat to internal validity in which an extreme performance on a test is followed by a less extreme performance.
Regression to the mean
What is the small subset of the population from whom you collect data called?
Sample
Which of the following would be given the rank of the highest form of evidence?
Systematic review of randomized controlled trials
Which threat to internal validity refers to the behavioral effect introduced on research subjects when they know they are being observed? ___________________________
The Hawthorne Effect
Internal validity may be defined as:
The extent to which the independent variable effects the dependent variable
_______________ variables are uncontrolled factors other than the independent variable that that may influence the measures of the dependent variable, thus negatively impacting internal validity.
Confounding
In evaluating the method section of a research report, which is a very important question to keep in mind?
Did the author provide enough information that the study could be repeated?
_________________________is a threat to internal validity referring to the loss or dropout of subjects in a study.
Experimental Mortality
The only type of research that can manipulate treatments and establish a cause and effect is
Experimental Research
A study is designed to investigate the effects of different brands of toothpaste (Colgate vs. Crest) on the prevention of cavities. What is the independent variable and dependent variable?
IV:brand of toothpaste DV: number of cavities
A researcher wants to compare a dosage of 1200 mg vs. 2400 mg of ibuprofen on delayed onset muscle soreness (DOMS) following an intense bout of exercise. Identify the independent and dependent variables.
Independent variable: dosage level; dependent variable: measure of DOMS
The extent to which the results of a study can be attributed to the treatments used in the study is the definition of what kind of validity?
Internal
The independent variable:
Is the variable that is manipulated to see if it affects behavior or performance
Which threat to internal validity occurs when members of the control group adopt a competitive attitude towards the experimental group, thereby negating their status as controls? ______________________
John Henry Effect
_________________________ is the threat to internal validity that refers to the physiological processes occurring within the participants that could account for any changes in their behavior.
Maturation
From least precise to most precise, list the four levels of measurement.
Nominal, Ordinal, Interval, Ratio
This is another word for a single observation:
a data point
A researcher conducts a study on the effectiveness of plyometric exercise by comparing sport teams that use this method with teams that do not. The researcher expects the teams that utilize plyometrics to show higher gains in power production. This statement is:
a hypothesis
A null hypothesis is
a statistical hypothesis that assumes that there is no difference among the effects of treatments
____________________ is the likelihood of an event occurring under specific conditions
absolute risk
This question pertains to the following study: "A researcher wishes to determine the effects of an outdoor adventure summer camp on the self-concept of inner-city boys. Boys are randomly assigned to the summer camp and to a control situation. The experimental treatment is for three months. A secondary purpose is to see if age (ages 6, 9, and 12) affects the relationship of the camp effects and self-concept."The independent variable is
adventure summer camp
What does 1 - b represent?
alpha level
What is another term for the mean?
arithmetic average
This threat to external validity is whether a subject will perform in the same manner under experimental conditions as they would in the real world.
artificial nature of experimental condition
This is the value that best represents an entire group of scores.
average
In the following example, what is the dependent variable? Does protein intake improve biceps circumference in male weight lifters?
biceps circumference
This question pertains to the following study: "A researcher wishes to determine the effects of an outdoor adventure summer camp on the self-concept of inner-city boys. Boys are randomly assigned to the summer camp and to a control situation. The experimental treatment is for three months. A secondary purpose is to see if age (ages 6, 9, and 12) affects the relationship of the camp effects and self-concept."The dependent variable is
self-concept
_________________________ of measurement is the degree to which small differences can be detected
sensitivity
What does the term "skew" mean?
significantly distort
If a distribution is "significantly distorted" what is this called?
skew
What is another term for variability?
spread or dispersion
Administering the same test on 2 or more occasions via the test-retest method, is a way of establishing which subset measure of reliability?
stability
What is the most common measure of variability?
standard deviation
Which measure of variability is a measure of the average distance from the mean?
standard deviation
Which of the following is not a measure of central tendency?
standard deviation
The ability of a study to detect a real effect or relationship, if it actually exists is the definition of:
statistical power
In experimental design, when comparisons are made of groups that have been selected on the basis of their extreme scores, the posttest means of the groups tend to move toward the mean of the entire population from which the extreme groups were selected. This threat to internal validity is called
statistical regression
This threat to external validity occurs when the unique characteristic of the subjects in a study makes the treatment effective only for those that possess that trait.
subject and treatment interaction
At the top of the research/evidence hierarchy are ____________________, which collect, review, and summarize all empirical evidence that fits pre-specified eligibility criteria, and ___________________, which is a statistical procedure for combining data from multiple studies.
systematic reviews; meta-analysis