5022 Final

Why is it important to assess, one at a time, each of the components of measurement?

Each feature of measurement provides information that is prerequisite to understanding what the data say

Talking about investigator behavior in the same way that we approach any other behavior of interest is useful because it can help us:

Identify antecedents and consequences that have influenced investigator behaviors and methodological decision-making

Generality has to do with the _______ of experimental interpretations under circumstances that are different from those that generated the data.

meaningfulness

A within-subject, single-baseline design that uses AB and reversal sequences to identify effects of manipulating a specific parameter of a procedure is called a(n) ______.

parametric

The field of study that focuses on evaluation methods and test theory is called ____.

psychometrics

We assess the ______ of data to make decisions about validity, reliability, and accuracy of data.

quality

When evaluating a study, an investigator must be satisfied about the _______ of data.

quality

______ is a measure of variability defined by the highest and lowest values in a data set.

range

What is the defining distinction between control and experimental conditions?

The presence of the independent variable

Shanice is a BCBA who is graphing her client's data. Why are graphs important for her clinical work?

All of these are reasons graphs are important -Data encourage her to make the most effective treatment decisions -Data influence her interpretations of results of clinical interventions -Data serve as stimuli that influence her reactions to what is going on with her client's behavior

______ is the subject matter for all behavior analysts.

Behavior

When researchers choose to limit observer's access to information about the study as a way of minimizing the chance that it might influence their judgments, we refer to observers as being ______:

Blind

When data contain one or two outliers, the investigator should do what to the vertical axis?

Change the values on the vertical axis to accommodate the outliers and keep them in the correct spatial relation to the remaining values

All of the following are steps in designing a human observation procedure, except:

Collecting interobserver agreement data to assess accuracy and reliability

Other disciplines outside behavior analysis often address research questions concerning:

Comparisons of groups of people

An _______ is a relatively brief period of responding defined by the relatively frequent occurrence of one or more specific response classes and which is distinguished from other such bouts by relatively extended periods in which the target responses do not occur.

Episode

You are attempting to help your best friend stop smoking. In order to tell if your intervention works, you decide that you'll need some baseline data on the number of cigarettes that he smokes per day. You have some of the same classes, so you decide to record the number of cigarettes he smokes from 8:00am to 11:00am on Mondays and Wednesdays. In this example, you are using:

Incomplete observation

Jesslyn is a 5-year-old little girl who is just learning how to read. She is working with her teacher on letter-sound correspondences, blending sounds, sounding out words, and saying them at a normal pace. In this example, what is the response class?

Jesslyn's reading behavior

Katie wants to decrease her behavior of swearing. She arranges a contingency in which she will pay ten dollars to her parents every day that she swears. In this example, what is the unit of analysis?

Katie's swearing behavior

Lisa is a practitioner working with a child who has difficulty transitioning from one activity to the next. She is interested in improving the child's delay between being told to switch activities and starting the next activity. Which of the following dimensions would be most important for her to measure?

Latency

Each of the following terms are ways of referring to within-subject designs, except:

N=2 designs

In which designs does a researcher take steps to ensure treatment and control groups are matched on key variables?

Non-randomized controlled trials

______ occurs when participants in one group are treated differently by researchers than participants in the other group.

Performance bias

Which of the following would be considered a behavior?

Reading a book

The ordering of conditions may result in ______, which may make responding more useful in identifying the effects of the next condition.

Sequence effects

A researcher has two groups of participants, one group receives monetary compensation for completing exercise activities and the other group does not. All individuals in both groups are weighed weekly. What is the dependent variable in this study?

The weight (in pounds) of the participants

Researchers should begin data analysis:

as soon as there is data to analyze

_________ occurs when there are differences in the way dependent measures are administered to groups.

assessment bias

The rule for whether you draw a line connecting a Tuesday data point to a Thursday data point when there was no observation on Wednesday is: if the behavior could have occurred but was not observed ______ the data points. If the behavior could not have occurred ______ the data points:

connect; do not connect

All of the following are dimensions of individual responses, except:

frequency

It's important for behavior analysts to understand group-designs so that they are _______ consumers.

informed

Regardless of our level of confidence, there is no way to know whether our ______ are correct, much less whether they will hold up under different circumstances.

interpretations

If an investigator wanted to compare the effects of different treatments for a single behavior of a single individual, they would most likely use a(n) ______ design, which involves switching between two or more treatment conditions rapidly.

multi-element

A meta-analysis analyzes data from _______ studies.

several

It is important to remember that ______ data can simultaneously reveal and obscure important features of the data.

summarizing

Duration, latency, and interresponse time all include ______ dimensions of behavior.

temporal

The task is not just to interpret the data, but to interpret:

the entire experiment

Allen is a practitioner who would like to calculate the rate of his client's spontaneous requests. To do so, he needs to divide the count he measures by a measure of _______.

time

A pattern of responding involving change from one steady state to a different steady state is called a _____.

transition state

If a study is well done, how many participants are needed to justify conclusions that the data are true:

1

Below are the results of a whole-interval recording procedure. What is the occurrence agreement score? Observer A: XX X XXXX Observer B: XX XXX XXX

67%

Below are the results of a partial-interval recording procedure. What is the interval agreement score? Observer A: XX X XXXX Observer B: XX XXX XXX

70%

Of all the single baseline designs, the ____ design is the weakest for making conclusions about the effects of an independent variable.

AB

Each of the following is a type of descriptive statistic measure, except:

ANOVA

All of the following are ways of adding a temporal requirement to a response class definition, except:

Add a requirement for the amount of times that a behavior must occur within a specified time period

When an experiment's question, procedures, and write up suggest that the investigator's primary goal was to generate support for a predetermined conclusion, it can be called ______ research:

Advocacy

All choices made by investigators have an effect on ___________.

All of the above can be influenced - Future choices the same investigators will make - What results of the investigation show - Conclusions that can be made based on the results

Pia is a BCBA practitioner and she has developed a treatment protocol for reducing a problem behavior with one of her clients. Which of the following should Pia consider before implementing her treatment?

All of these are important considerations for clinical interventions - How can extraneous factors be controlled? - How can implementation be arranged so it isolates the effects of the treatment? - Could there could be sequence effects that impact responding?

Summarizing data across participants is problematic because:

All of these are problematic limitations -a group "effect" not found in individual records should not be considered a sole result of treatment -there is no such thing as a "group" organism -there are limits of what can be said based on group data

______ is a method of arranging comparisons between control and experimental (or treatment) conditions in which different groups of subjects are exposed to control and experimental conditions so that the data represent the combined performance of individual participants who have experienced only one of the conditions.

Between-groups design

With regards to typical notations of within-subject designs, the C in an ABCAB design stands for which condition?

Condition 2

The first step in designing an automatic observation procedure is to:

Determine what changes in the environment consistently result from responding

When assessing measurement procedures, what is the first priority?

Determining accuracy of data

What is the goal of developing and phrasing experimental questions?

Developing a question whose subsequent experiment will generate data more revealing and useful than produced by any other previous question

A personal trainer records the number of miles her client can run when he first comes to her for help. After a month of training, she again records her client's performance to see if he has improved his stamina. In this example, the personal trainer is using what kind of measurement?

Direct

Which of the following research questions would be best addressed with a group-design?

Does an intensive ABA therapy treatment package alleviate symptoms of autism?

Cam is recording how much time it takes his client to complete 20 multiplication problems. Cam is recording what dimension of behavior?

Duration

In an attempt to avoid biases and preconceptions, an analytical style known as ______ may be used to focus on discovering order and structure in the data.

Exploratory data analysis

One of the most common constraints on the sensitivity of a behavior comes from:

Extraneous variables

The scientific discovery of behavior includes which of the following activities?

Framing questions, measuring behavior, analyzing data, drawing conclusions

Each of the following is an example of a behavior analytic assessment tool except:

Functional behavior analysis

Extra-experimental contingencies such as ______, ______, and ______ can lead to questions that serve personal interests more than the needs of the field:

Grants, consulting contracts, reputation

The ______ is the centerpiece of experimental procedures, and the experimental question's most important role is guiding its selection:

Independent variable

The control condition controls for all of those factors in the experimental or treatment condition that are not the ___________.

Independent variable

A teacher conducts an interview with the parents of one of her students and asks them how they think their child has responded to the change in the classroom rules. In this example, the teacher is using what kind of measurement?

Indirect

Scientists always prefer direct measurement over indirect measurement because:

Indirect measurement requires them to make assumptions between what is measured and what it is supposed to represent

__________ refers to the appropriateness of attributing a causal role to independent variables.

Internal validity

The control condition serves two purposes. The first is to establish general conditions under which participants will behave. What is its second purpose?

It controls for all of the factors in the experimental condition that are not the independent variable

Which of the following is a limitation of what duration describes about behavior?

It does not include countability

How does the experimental question help the researcher design measurement procedures?

It helps the researcher decide how long and how often observational sessions should occur

What is the problem for the study of behavior with using data from groups of subjects who are exposed to either the control or experimental condition alone?

It leads to data that mixes behavioral variability with intersubject variability

What are the methodological consequences of assuming that behavioral variability is extrinsic?

It requires the investigator to focus throughout the study or clinical treatment on specific features of the relations between behavior of the individual and the environment

______ scales allow descriptions of events that show how much they differ in terms of equal intervals between values.

Linear interval

What advantage does automatic observation have over human observation?

Machines are much better at doing the same task repeatedly without being influenced by anything outside of their programmed parameters

In RCTs, the random assignment is assumed to _______.

Maximize internal validity

Megan is a BCBA Practitioner and she discovered some interesting clinical findings with one of her clients. She is interested in studying these results more. Which of the below is her best option?

Megan could consider conducting a more systematic investigation and utilize these findings as a question for further study

Johnston and Pennypacker list three objectives data analysis should meet. The first two are: (a) identifying and describing data that may answer the question, and (b) discovering relationships in the data that were not anticipated and that may be interesting. What is the third objective?

Modifying the initial decisions about how the experiment will be conducted as the study proceeds

The key for determining experimental control in the multiple baseline design is for responding to change in _______.

Only the baseline experiencing the treatment condition

One tactic for dealing with variability is to reduce variability by isolating and controlling extraneous factors in the environment. What is the second?

Producing variability in responding by manipulating independent variables

In behavioral research, analyzing the data using different techniques serves all of the following objectives, except:

Provides the researcher with information that will allow him or her to reject or accept the null hypothesis

What is a risk of using only the research literature as a basis for experimental questions?

Questions that emerge from published studies tend to pursue the general directions already established in the literature

The _______ design involves assigning participants to groups based on whether they score above or below some threshold criterion value.

Regression discounting

________ addresses the question of if experimental procedures are repeated, will the same effects be obtained. While ______ addresses the question "if experimental finding are used under different circumstances, will the same kind of effects be obtained?"

Reliability; generality

______ is useful because it helps the researcher to assess the reliability of the original findings, or the extent to which they might be obtained under somewhat different conditions.

Replication

When displaying time on the horizontal axis, why is it important to represent time continuously?

Representing time in a discontinuous manner can hide variability in the data

What is the difference between the primary focus of researchers and practitioners?

Researchers try to discover relations between environment and behavior. Practitioners focus on improving lives.

What are the three general types of response classes?

Respondent, operant, and discriminated operant

Multiple baseline designs use two or more baselines in a coordinated way to allow _________ comparisons within and across baselines.

Responding in control versus treatment

A ________ refers to a collection of individual responses that have common sources of influence in the environment.

Response class

_______ are the tangible or intangible environmental effects of responding that are more than transitory in duration.

Response products

A response class is a grouping of individual responses that share those commonalities included in the definition of the class. ________, then, are the individual instances of behavior that make up each class.

Responses

A practitioner wants to demonstrate if reinforcing appropriate statements would reduce a client's disruptive talking (found to be maintained by attention). To evaluate empirically, it would be best to use which type of design?

Reversal design (ABAB)

Why do we define behavior?

So that we can study or change behavior

What does it mean to say that behavior is part of the interface between the organism and the environment?

That behavior is not something an organism possesses, but rather an interaction between the organism and the environment

The most notable advantage of using participants as observers is:

That they are always present when the behavior occurs

Billy and his older brother, Alex, get into an argument over who is going to get to play the video game next. Alex becomes angry at Billy and starts yelling and punching him, leaving bruises on Billy's arm. In this example, what is the response product?

The bruises on Billy's arm

In order to create meaningful comparisons between responding under control versus treatment conditions, at least two key requirements must be met. First, each participant must be exposed to both control and treatment conditions. What is the second requirement?

The data for each participant must be measured and analyzed separately

What are the two requirements for evaluating the accuracy of a set of observations

The data must represent physical events, and it must be possible to measure these events directly

How is it that an investigator (researcher or practitioner) both controls and is controlled by the subject matter?

The investigator must control the factors whose effects are under study and other outside factors, while the data from the study serve as a prompt for any needed changes

What must be done to legitimize the use of indirect measurement?

The investigator must present clear experimental evidence about the relationship between what is being measured and what it is supposed to represent

How does the experimental question guide the selection of participants?

The question should suggest certain participant characteristics, ethical and logistical considerations, and behavioral characteristics

What are the two general kinds of information that the different types of replication provide?

The reliability and generality of the findings

Which of the following is not an example of a professional contingency?

The response class definition that was used

In this style of research, a study is designed to fit into a predetermined position in a larger research program or area of literature:

Thematic

Johnston and Pennypacker discuss all of the various influences on question-asking behavior, except:

Theoretical orientation

If a researcher is measuring the duration of a target behavior and achieves a steady state of responding, they can then conclude what about the frequency of that target behavior?

They cannot make any conclusions about the frequency of the target behavior

Controlling for extraneous variables is most important for which type of within-subject design?

This is important for all designs - Changing criterion - Reversal - AB

Perhaps the most important role for any behavior that will serve as the dependent variable is:

To be sensitive to the independent variable

The overarching goal of behavioral measurement is:

To produce data that will guide correct and meaningful interpretations

You are working with a young child with autism on teaching them how to request a glass of water. You define the child's requesting-water behavior as any time the child says "Water, please." In this example, what kind of definition is being used?

Topographical

_______ response class definitions define response classes based on the form of responses in three-dimensional space.

Topographical

______ is the extent to which the independent variable is consistently implemented as designed.

Treatment integrity

One of the key differences between statistical and visual analyses is that statistical analysis is done after the data are collected while visual analysis is an ongoing activity throughout the experiment.

True

If the target behavior is directly measured, the data are automatically:

Valid

A definition of behavior is itself ______.

Verbal behavior

Whether developed by a researcher or a practitioner, perhaps the most important fact about experimental questions is that they are:

Verbal behavior

A researcher has two groups of participants, one group receives monetary compensation for completing exercise activities and the other group does not. All individuals in both groups are weighed weekly. What is a potential extraneous variable to control for in this study?

What participants eat while taking part in the study

When should data be discarded?

When data are known to violate basic standards of measurement or are not collected under intended conditions

According to the intra-organism nature of behavior, the term "group behavior" is misleading because:

a group is not a biological organism and therefore cannot behave

When we interpret a study our conclusions about what happened and what the study means probably fall short of perfect __________.

accuracy

Correlating results of two different forms of the same assessment administered to the same group of individuals is called ___________.

alternate-form reliability

Bobby has trouble sitting still in class, and a behavior consultant works with a teacher to implement a clinical program in which she praises Bobby when staying in his seat. Bobby's sitting behavior increases, and the teacher concludes to the behavior consultant that her praise was responsible for the change. The teacher does not realize that Bobby has started taking medication that causes fatigue. In this example, the medication is serving as:

an extraneous variable

In a concurrent multiple baseline design, two baselines occur ________.

at the same time

In single group pretest-posttest design, the dependent measure is administered to all in the group when the study begins and after they have __________.

been exposed to a treatment

A behavior analyst is interested in using a multiple baseline design to evaluate the effects of praise and prompting for a child learning different types of signs in sign language. Based on this information, the behavior analyst should use the multiple baseline across _____.

behaviors

The only way to assess accuracy is:

by comparing observed values with true values

A type of observational study design that is often used in epidemiological research is the ________.

case control study

Most applied behavior analysts are not researchers, but work to:

change individual's behaviors in socially significant ways

A(n) ______ research design is a useful design for investigators interested in gradual decreases in goal levels for the target behavior.

changing criterion

Researchers and practitioners examine behavioral variability using all of the following approaches, except:

comparing simultaneous but independent observations from two or more observers

Although ______ observation is an ideal approach, it does not guarantee that the resulting data will be accurate.

complete

By giving a participant repeated exposure first to the baseline condition and then to the intervention condition, the researcher is trying to get a graphical picture of responding under each condition that is ______ and ______.

complete; representative

The extent to which results produced by a new assessment correspond with results of a well-established assessments of the same domain is called _____

concurrent

The extent to which an instrument is shown to assess the idea or theory that it purports to measure is called ________.

construct

The extent to which scores on an assessment represent the materials it purports to measure is called ________.

content

By delaying or temporally staggering the introduction of the intervention condition in the second baseline, the investigator creates an opportunity to compare responding under the ______ condition in the second baseline with responding under the ______ condition in the first baseline:

control; treatment

Jane is designing an intervention to decrease vocal outbursts of one of her clients in a school classroom. She's interested in decreasing the number of outbursts per day. The most important dimension for her to consider measuring is ___________.

count

In the study of behavior, measures of frequency generally take the form of the ratio:

cycles of a behavior occurring over some period of time

Generality addresses the question of "if experimental findings are used under _________ circumstances, will the same kind of effects be obtained?"

different

A dimensionless ratio is a unitless number that results from calculations whose components share the same:

dimensions

Measurement that involves measuring the same event that you are drawing conclusions about is called ___________

direct

What we know about behavior suggests that practitioners and researchers should

do all of the above - analyze behavior at the level of the individual organism - measure a target behavior a number of times under each experimental or treatment phase - compare data across baseline and treatment conditions

Joe has a client who engages in bouts of high-pitched screams during sessions and he would like to target this for intervention. Given that screams occur in rapid succession, the dimension of __________ can be useful for Joe to measure.

duration

Measures of clinical or practical significance are referred to as ________.

effect sizes

The phrase ______ refers to how researchers arrange comparisons between control and experimental conditions so as to permit inferences about any effects independent variables may have on responding.

experimental design

_________ refers to the extent that the results of a study can be generalized to other circumstances.

external validity

The length of overlap in a multiple baseline design should be long enough to allow for effects of _______ to emerge in the control phase.

extraneous variables

All things considered, a study is either good enough to warrant conclusions or it is _________.

fatally flawed

The primary challenge in interpreting a project is deciding how each of its _______ might have affected data.

features

The goal of experimentation is to learn enough about the effects of the independent variable on the target behavior to show that particular changes in responding are a function of the independent variable and nothing else. This result is called a(n) ______.

functional relation

Suppose that every time Johnny asks a question, the teacher answers it. Also suppose that he asks a question in class except when his particular teacher is present. This example demonstrates a(n) ______ between Johnny's question-asking and his teacher answering his questions.

functional relationship

When selecting dimensional quantities to measure, a researcher or practitioner should take into consideration each of the following, except:

how long do I plan on collecting data?

Other approaches to studying and explaining behavior (not behavior-analytic) tend to be based on:

hypothesize inner processes

Identifying transition and transitory states is a matter of:

identifying the steady states preceding and following the transition

A multi-element design requires an investigator to be confident that the transition in responding between control and treatment conditions will be ______.

immediate

______ observation is not a poor approach, as long as the researcher is able to arrange periods of observation to yield data that provide a good description of what responding would look like during unsampled time periods.

incomplete

Controlling extraneous factors to reduce behavioral variability is necessary in order to be sure that any change in responding during a particular phase is due only to the ______.

independent variable

The researcher or practitioner must be sure that data being compared fully represent the impact of each condition, so that any differences in responding that are seen may be attributed to the ______.

independent variable

Although two different graphical analyses of the same data set may be constructed correctly, they would likely evoke different _______ from viewers.

interpretations of results

You are working with a 4th grader, Sally, who has difficulty reading. One of the measures you use to evaluate your interventions is to record the amount of time between finishing reading one word in a sentence and starting to read the next word. This is a measure of:

interresponse time

Because behavior is a(n) ______ phenomenon, orderly relationships between behavior and environmental variables can only be seen clearly by looking at the behavior of individuals.

intraorganism

A nonconcurrent design is especially problematic for strong conclusions because:

it is essentially two (or more) independent ab comparisons

While eliminating extraneous variables to help manage behavioral variability has many advantages, it can also be problematic. All of the following are disadvantages associated with this tactic, except:

it is so difficult to do that the investigator's time is often better spent on other issues

The control condition is often presented before the experimental condition for all of the following reasons, except:

it provides a better comparison between the two conditions than if the order was reversed

Group-designs are also referred to as _____ designs.

large-n

Generally, the ______ often the behavior occurs, the more frequent or longer the observation periods should be in order to provide a good sample of responding.

less

______ interval scales allow descriptions of events that show how much they differ in terms of equal ratios between values:

logarithmic

When describing results of a study it is important to only describe the dimensions of behavior that were _______________.

measured

Practitioners must understand research methods because they ______.

need to be critical consumers of research for making clinical decisions

What was the experimental design used in the Garcia et al. (2016) study?

nonconcurrent multiple baseline

Although ______ criteria for deciding when to change phases are risky, there is no denying that researchers or practitioners might sometimes feel it necessary to limit the length of phases.

nondata

An IQ score is an example of a ____________ assessment.

norm-referenced

Data points should ______ connected across phase changes.

not be

A value that results from observing and recording procedures is called a(n) ______ value.

observed

Each of the following statements describe why it is important to carefully select dimensions of behavior for measurement, except:

only one or two dimensions can be chose per investigation

When defining behavior we should have a clear understanding about the nature and limits of behavior (what it is and what it isn't) because

our colloquial history is embedded with mentalism

Interresponse time can be an important aspect of responding, especially when ______ of responding is of interest.

pace

A behavior analyst is interested in using a multiple baseline design to evaluate the effects of a of a time out procedure for multiple children with a history of aggression in a classroom. Based on this information, the behavior analyst should use the multiple baseline across _____ design.

participants

The following is NOT a safety skill that was mentioned by the Garcia et al. (2016) as having used BST to train the skill.

poison safety

In hypothesis testing, researchers aim to ______ the null hypothesis.

reject

In psychometric terms, a measurement of how much error is present in assessment results is referred to as _____.

reliability

Interobserver agreement does not provide information about either ______ or ______.

reliability; accuracy

Ron, a behavior analyst, uses a multiple baseline design to examine the effects of a social skills training program with three different individuals. Maria uses the same procedure but receives different results. In this example, Maria demonstrated the use of ______:

replication

The form of replication that stems from the steady state strategy is:

replication across sessions

The main difference between single and multiple baseline designs is that multiple baseline designs _______.

require more than one participant, behavior, or setting for comparison

Reversal designs are informative only when:

responding reverts to the original baseline pattern after the intervention is withdrawn

While a research question can influence interpretations of data, the question should not discourage examining data for ______ discoveries.

serendipitous

A behavior analyst is interested in using a multiple baseline design to evaluate the effects of a token board on academic engagement and on-task behavior in both math and reading classes for a child in 3rd Based on this information, the behavior analyst should use the multiple baseline across _____ design.

setting

Some of the problems associated with discontinuous observation can be minimized by selecting very ______ intervals.

short

______ responding across sessions is a strong indication that the data fully represent the effects of that condition and that the contribution of extraneous factors is minimal or at least constant.

stable

A _________ assessment ensures comparisons reflect actual differences in behaviors of individuals of interest instead of differences in procedures and individuals scoring assessments.

standardized

______ criteria usually specify a limited amount of variability that will be permitted over a certain number of data points.

statistical

Viewing data as a(n) ______ problem means that the choice of data analysis techniques is not just a matter of whether a particular statistic or graph is correctly calculated or constructed. The more important issue is whether it encourages the researcher to make good decisions and draw sound conclusions.

stimulus control

A steady state of responding suggests that extraneous influences are minimal and:

that any transition from the initial effects of the condition are complete

If a study is well designed and conducted, the variability between phases ideally represents the effects of ________.

the independent variable

If you repeatedly exposed each subject to a condition in an effort to control or eliminate extraneous influences and allow the condition to fully represent its effects on behavior, you would be using:

the steady-state strategy

Abby is a behavior analyst practitioner who provides ABA services to individuals with autism. As a practitioner, what best describes her "bottom line":

to improve lives by changing behavior

A relatively consistent change in data in a single direction is called a(n) ______.

trend

A trend that has no obvious explanation is _________ for researchers and practitioners.

troublesome

A behavior analyst supervisor asks a therapist to record on a data sheet the number of math problems a client completes during treatment sessions. In an effort to evaluate the data reported on math completion, the supervisor collects the math sheets periodically and records the number of math problems completed. She then compares the math sheets to the number recorded by the therapist on the corresponding data sheet. The behavior analyst supervisor is recording:

true values

In the most general sense, ______ is the subject matter of all sciences.

variability