HomeBxLogDana Do’s: Mean or Median? Choosing the Right Level Line to Interpret Graph Data Dana Do’s: Mean or Median? Choosing the Right Level Line to Interpret Graph Data February 27, 2025 Being able to interpret graph data is an important skill for the exam. One of the properties of inspectable behavior-change on a graph is the level line. This line represents the degree to which the data values converge. This is the horizontal line that looks like it’s going through the middle of the data point values. Think of the level that you would use to see if a picture is hanging straight. This is not just an arbitrary line. It requires math, and knowing which mathematical equations is the most appropriate for a specific set of data. There are two ways to establish a level line: one is by taking all the data points and calculating their average. This is known as the mean level line. A level line that represents the average value of the successive data points. The other way to establish the level line is by identifying the middle value of all the data points. For example, if you put all the values in order, from smallest to largest, what number is in the middle? That number represents the placement of the median level line. Think: mean equals average, and median equals the middle value. So when should the level line be based on the mean, and when should it be based on the median? If the data path is relatively stable, then the mean level is the way to go. It is an average of all the data values. But if the data is variable, with extreme outliers in either direction, then a good way to offset the influence of those outliers which would sway the data, is to use the median level line. 6th Edition TCOC. Measurement, Data Display, and Interpretation C.11 Interpret graphed data. MiniBig C D FStreaming Lecture Series Related Content Dana Do's: Two Procedures for Calculating Duration If you’re looking for data on how long a behavior occurs, duration is the name of the game. However, as PTB founder Dana Meller explains, there are two methods for ensuring and reporting duration that future BCBA®s need to know. Dana Do's: Three Characteristics of Operational Definitions Being able to discriminate good operational definitions is essential, especially when it comes to correctly answering exam questions. PTB founder Dana Meller breaks down the three characteristics of operational definitions and shares a handy acronym to help make it more memorable.Dana Do's: What's the Difference Between Continuous and Discontinuous Measurement? It’s all too easy to mix up continuous and discontinuous measurement procedures. Need some help discriminating between the two? Get clarity with help from PTB founder Dana Meller.Y-axis The vertical axis of a graph, which displays the quantitative values of the measured behavior (e.g., count, percent correct).Whole interval recording A time-sampling data collection method used to estimate the overall occurrence of a behavior by measuring the number of intervals during which the behavior occurs for the entire duration of…Trials to criterion The specification of the number of response opportunities required to achieve a pre-specified level of performance criteria.Validity Measurement is trustworthy when the measurement that produces data is applicable and specific to the target behavior of interest and the relevant dimension of that behavior; in other words, you…Variability On a line graph, the degree to which the data points bounce around the data path.X-axis The horizontal axis of a graph, which frequently represents the dates or sessions across which data were collected.Topography Measurement that describes a behavior’s physical form and shape.Training duration The predicted amount of training time needed for a client to achieve independence and mastery in program goals.Trend On a line graph, the overall direction of the data path.Temporal extent A measure of the duration of time that a behavior occurs from onset (i.e., start) to offset (i.e., end).Temporal locus When measurement refers to the point in time that the behavior occurs (latency, interresponse time).Standard celeration chart A standardized process for charting and analyzing how the rate of behavior changes over time.Split-middle line of progress A line drawn on a line graph that represents the general direction of the data; used to visually analyze the overall trend of the graphed data.Scatterplot A chart and measurement system that displays patterns related to behavior and specific time and setting variables.Scale break Specific marks on, or breaks in, the x-axis (i.e., horizontal axis) indicating the time periods during which data were not collected.Reliability Measurement is trustworthy when the degree to which repeating a measurement procedure under the same conditions produces the same result.Product measures A measurement of a target behavior taken by measuring the lasting environmental changes produced by that behavior, rather than counting actual occurrences of the behavior. (E.g., test scores, completed chores,…Rate A derived measure of behavior that involves calculating the number of occurrences of a given response within a given period of time (e.g., number of mands per hour). Answers the…Quarterly intersect line of progress A method of analyzing the trend of the data on a line graph that involves dividing the data into two equal parts and establishing intersections for mid-rate and mid-date points…Percentage A derived measure of behavior that depicts the proportional quantity of the number of times the behavior occurred out of the total number of opportunities for that behavior to occur…Planned activity check A time-sampling data collection method used to estimate the overall occurrence of behaviors of a group of individuals by measuring the number of intervals during which the behavior occurs at…Operational definition An objective, clear, and complete description of target behavior.Occurrence data A measurement of behavior that represents its repeatability and countability.Partial interval recording A time-sampling data collection method used to estimate the overall occurrence of a behavior by measuring the number of intervals during which the behavior occurs at any time within an…Observer drift When observers collecting data have a shift/drift in how they interpret the operational definition of the target behavior that affects the validity of their data.Observer reactivity When an observer’s data collection or performance is influenced by the awareness that they are being monitored and evaluated.Magnitude The measurable dimension of a behavior’s strength, force, intensity, and/or severity.Momentary time sampling A time-sampling data collection method used to estimate the overall occurrence of a behavior by measuring the number of intervals during which the behavior occurs at the end of an…Measurement artifact Data that represents an unwarranted and misleading picture of behavior because of how it was measured, typically a product of time-sampling, limiting measurement scales, or poorly scheduled measurement periods.Measurement bias When an observer’s measurement is influenced by an expectation or belief they hold rather than what actually occurred.Line graph A chart used to display the occurrence of behavior across specific time periods. Each data point shows the level of some quantifiable feature of the dependent variable in relation to…Mean level line A horizontal line on a line graph established by calculating the average of the graphed data points; used to signify the degree to which data points converge on the y-axis.Median level line A horizontal line on a line graph established by calculating the median of the graphed data points, used to signify the degree to which data points converge on the y-axis.Latency The measurable duration of time between the onset or appearance of a stimulus and the initiation of the response.Interresponse time (IRT) A measurable duration of time that elapses between two consecutive instances of a response.Interobserver agreement (IOA) A measurement of the degree to which two or more observers report the same values when observing and collecting data for the same behaviors/events.Level On a line graph, the degree to which the data points on the y-axis converge, established by calculating the mean or median of the graphed data points.Indirect measures of behavior A measurement of behavior that is not based on an actual observation of the behavior itself, but a secondhand account of the behavior’s occurrence (e.g., rating scales, permanent product, descriptive…Equal interval graph A graph, used to analyze the effects of treatment on a target behavior over time, that visually represents data in which the distance between any two consecutive points on the…Environmental constraint Something within a person’s environment that can be a barrier to the effectiveness of behavior analysis-based services.Duration Hint: Duration answers the question, “How long did that behavior last?” A measurable dimension of the amount of time that a behavior persists from onset (i.e., the start) of the…Discontinuous measurement A measurement procedure in which a sample of a target behavior is recorded during a specific period of time, instead of every instance of the behavior.Dosage The intensity, frequency, and duration of the behavioral treatment provided to a client.Direct measures of behavior A real-time measurement of a behavior as it is occurring, resulting in each instance of the observed behavior being recorded.Data path A line that connects successive data points within a specific phase of treatment or condition on a graph.Data points Specific symbols on a graph that represent the measurement of a behavior, recorded during a specific observation period.Data The result of measuring a quantifiable aspect of behavior, used to assess and evaluate behavior and behavior analysis-based services.Count A measurement that directly summarizes the number of occurrences of a given response/behavior. Answers the question: How many times did the behavior occur, or how many of something were produced?Continuous measurement A measurement procedure in which every instance of a target behavior is recorded during a specific period of time.Cost-benefit analysis An analysis of the potential costs and benefits of implementing a behavioral technology (e.g., an assessment, or intervention).Cumulative record A continuous graph to which new data are added, visually displaying the cumulative total of the behavior over time. Hint: Think of this as a visual display of a collection,…Condition change lines Vertical lines, drawn upward from the x-axis to the top of the graph, that separate the points in time of different independent variable conditions or important changes within a treatment…Celeration A measure of the change (i.e., increase or decrease) in the rate of a behavior over a period of time. Answers the question: How did the rate of behavior change…Bar graph A chart that displays data using rectangular bars or columns that represent unrelated discrete sets of data with a common dimension.Accuracy The degree to which what was measured (observed value) is representative of what actually occurred (true value); in other words, the data was measured correctly.Dana Do's: All the Validities in ABA, Explained PTB founder Dana Meller helps connect each of the validities to the validity of this explanation.Dana Do's: Why IOA Math Should Not Intimidate You PTB co-founder takes some of the fear out of the interobserver agreement math with simple tips that can help narrow your discrimination.Dana Do's: How to Define the Markers of Trustworthy Measurement PTB co-founder goes into the three factors that define trustworthy measurement-- "validity", "reliability" and "accuracy". But what's the difference between each? Dana explains.Dana Do's: How to Decipher the Many Forms of Validity It's particularly meaningful to be able to tell validity, social validity, internal and external validity apart. PTB co-founder Dana Meller has some tips to do just that.Dana Do's: Mean or Median? Choosing the Right Level Line to Interpret Graph Data Interpreting graphed data is an important skill to have, for the BCBA® exam and beyond. A fundamental part of this is the level line. PTB founder Dana Meller breaks down both methods for establishing a level line and when to use them.Dana Do's: How to Determine Preference of Tested Stimuli How do you determine the relative preference of tested stimuli during trial-based preference assessments? PTB Founder Dana Meller breaks it down.Dana Do's: Tips for Test Questions About Functional Analysis Tripped up trying to make correct discriminations when it comes to functional analysis? PTB founder Dana Meller has some tips to help you answer those tricky exam questions. Dana Do's: Six Direct Assessment Methods Looking to review direct assessment methods? PTB founder Dana Meller gets right to it with this quick explainer.Dana Do's: Exploring the Four Types of Reinforcer Assessments PTB founder Dana Meller discusses reinforcer assessments, which should not be confused with stimulus preference assessments.Dana Do's: Can Changing Criterion Design be Used to Evaluate Shaping Programs? Can can a changing criterion design be used to evaluate shaping programs? Well, PTB founder Dana Meller says, it depends. Dana Do's: Nine Considerations for Prioritizing Target Behaviors PTB founder breaks down each of the nine considerations for prioritizing target behaviors.Dana Do's: A Trick to Help Dissect BCBA® Exam Questions on Experimental Designs Experimental design tends to trip lots of people up. Here's an exam trick from Dana Meller that will help you breaking down questions on the exam.10 Positive Effects From Prioritizing Self-Care Self-care. It’s a bit of a broad term, and a total buzzword these days. It’s often used in the context of bubble baths and “unplugging.” But, at its core, self-care is about more than just “me-time.” It’s about taking care of yourself in a way that works best for you and your lifestyle. Dana Do's: How to Know if Your Study Activities are Effective How do you know if your BCBA® study activities are effective? PTB co-founder Dana Meller shares some key analysis that may help BCBA® exam candidates assess efficacy.Dana Do's: Careful About Getting Creative With Mock Exams PTB co-founder cautions candidates about using the actual BCBA® exam as a mock exam, listing all the reasons why you might want to reconsider getting creative with your mock exam prep experience.Dana Do's: Warning. Be Careful of Extremes. PTB co-founder Dana Meller sends an important warning for test takers. Watch out for extremes in exam questions and answer options.Dana Do's: How to Use Mock Exams in Your Study Plan I was recently asked if mock exams are useful in predicting how someone will do on the actual big exam. And, is repeating the same mock exam an effective study…Dana Do's: How to Discriminate Dependent vs. Independent Variables If You're Not a Researcher Not a researcher? How about some help discriminating between dependent and independent variables. PTB co-founder Dana Meller offers a few tips to make that distinction on the BCBA® exam.Breaking Down a BCBA® Mock Exam Question: Winning Measurement System to Record Client Tolerance to Losing Let's review and break down a BCBA® mock exam question about measurement techniques in ABA, specifically percentage of opportunity. PTB co-founder Dana Meller explains how to calculate the percentage of opportunities where the behavior is exhibited and why this method is superior to rate, count, and interval recording in certain situations. Refer to BCBA® Task List (5th ed.) Section C-3: Measure occurrence (e.g., count, frequency, rate, percentage).ABA Terminology Break Down ➠ Indicators of Trustworthy Measurement What are the three indicators of trustworthy measurement in ABA? PTB co-founder Dana Meller explains and why they ensure data accuracy and reliability. Refer to BCBA® Task List (5th ed.) Section C-8: Evaluate the validity and reliability of measurement procedures.MiniBig PTB MiniBig: Fast, Flexible, and Focused Exam Prep The PTB MiniBig enables BCBA® exam prep candidates to tailor their study needs by popping in on single sessions of the intensive PTB Big Exam Prep Workshop. Each 3.5-hour session, focused on specific sections of the Task List, includes a mock exam followed by real-time, live, interactive feedback and access to live session replays, without committing to the full workshop.Test your ABA Terminology ➠ Functional Assessment Procedures Focusing on ABC data collection, PTB co-founder Dana Meller discusses functional assessment procedures. Dana explains how to generate mathematical probabilities for target behaviors based on specific antecedents and consequences, providing a step-by-step guide to quantitatively analyzing the gathered information. Refer to BCBA® Task List (5th ed.) Sections F-7: Conduct a descriptive assessment of problem behavior and F-9: Interpret functional assessment data.Test Your Descriptive Assessment Skills ➠ ABC Recording Methods Get a comprehensive overview of ABC Recording Methods. PTB co-founder Dana Meller breaks down the two types, along with their differences, benefits, and practical applications. Refer to BCBA® Task List (5th ed.) Sections F-7: Conduct a descriptive assessment of problem behavior; and F-9: Interpret functional assessment data.Test your ABA Terminology ➠ Cumulative Record Calculations PTB co-founder Dana Meller reviews a question about using cumulative records and their significance in behavior analysis. Learn how to utilize cumulative graphs to track behavior over specific time periods and measure and calculate response rates for insightful data analysis. Refer to BCBA® Task List (5th ed.) Section C-11: Interpret graphed data.Dana Do's: 1-Minute Experimental Design Test Hack (you still have to study it though) PTB co-founder Dana Meller shares a huge secret to help break down experimental design questions. BCBA® Task List (5th ed.) Section D-3: Identify the defining features of single-subject experimental designs.Breaking Down a Mock BCBA® Exam Question: Reversal Design Variations With Only One Reversal Test your Experimental Design skills with PTB co-founder Dana Meller as she reviews and breaks down a mock exam question about reversal design variations that display only one reversal. Included is a description of A-B-A, B-A-B, and A-B-A-B reversal designs. Refer to BCBA® Task List (5th ed.) Section D-5: Use single-subject experimental designs (e.g., reversal, multiple baseline, multielement, changing criterion).Shortcuts to Understanding the Basics Behind Each Experimental Design Experimental design causes a lot of anxiety. PTB co-founder Dana Meller shares a few shortcuts to help on exam day, eliminating some answer options but also, more importantly, give you a head start on understanding the basics behind each design.Test your ABA Terminology ➠ Identify the Measurement System in This Scenario Test your measurement, data display, and interpretation knowledge with PTB co-founder Dana Meller as she discusses one specific measurement system that measures the effect of the behavior after its occurrence. Here, Dana details the two ways someone could implement this type of measurement system, provides examples of scenarios and a variety of corresponding measurement methods, and highlights some of the pros of utilizing this type of measurement system. Refer to BCBA® Task List (5th ed.) Section C-2: Distinguish among direct, indirect, and product measures of behavior.Dana Do's: Importance of Experimental Design Fluency PTB co-founder Dana Meller talks about the importance of being fluent in experimental designs, not just to pass the exam, but to be a good clinician as well. Ref Section D-3: Identify the defining features of single-subject experimental designs (e.g., individuals serve as their own controls, repeated measures, prediction, verification, replication).Break Down a Mock BCBA® Exam Question: Interobserver Agreement (IOA) Facts & Rules to Live By Test your Measurement, Data Display, and Interpretation skills with PTB co-founder Dana Meller as she reviews a BCBA® mock exam question about several #interobserveragreement (IOA) facts, with rules to live by. Here, Dana highlights a variety of important IOA benefits, as well as IOA percentage of agreement criteria details and the different reporting options. Refer to BCBA® Task List (5th ed.) Section C-8: Evaluate the validity and reliability of measurement procedures.Breaking Down a Mock BCBA® Exam Question: Identify a 3-Phase Reversal Experimental Design Test your Experimental Design skills with a breakdown of a BCBA® mock exam question about the identification of a three-phase experimental design. Included is a detailed comparison between four different reversal designs: ABC reversal, ABA reversal, BAB reversal, and ABAB reversal. As a bonus, Dana also provides examples of instances in which each of the reversal designs would be implemented. Refer to BCBA® Task List (5th ed.) Section D-5: Use single-subject experimental designs (e.g., reversal, multiple baseline, multielement, changing criterion).Test your ABA Terminology ➠ Pivotal Behavior vs. Behavior Cusp Test your behavior assessment knowledge with PTB co-founder Dana Meller as she compares and contrasts pivotal behavior vs. behavior cusp, providing several corresponding examples of each, as they relate to identifying the target behaviors that need prioritization for treatment. Refer to BCBA® Task List (5th ed.) Section F-3: Identify and prioritize socially significant behavior-change goals.IOA Mini Quiz Math can be daunting, but practice can help. You don’t have to be a math whiz to master the Interobserver Agreement formulas. Get more practice and gain confidence with the PTB IOA Mini Quiz. Updated for the 6th Edition Test Content Outline, the PTB IOA Mini Quiz features a new interactive format that simulates the test experience. Thirty fill-in-the-blank questions cover all 9 IOA formulas. Optional hints included with each quiz question assist you with the correct formula along the way. Check your work and collect data on your performance with the detailed score report. Test your ABA Terminology ➠ Interpret Descriptive Assessment Data Test your knowledge of interpreting descriptive assessment ABC data with PTB co-founder Dana Meller. Here she discusses conditional probability, including the rules that apply, and provides a step-by-step example using the calculation formula and how to report these data. Refer to BCBA® Task List (5th ed.) Sections F-7: Conduct a descriptive assessment of problem behavior; F-9: Interpret functional assessment data.Test your ABA Terminology ➠ Identify This Experimental Design Scenario Test your ABA terminology with PTB co-founder Dana Meller as she offers guidance to identify the specific experimental design relating to a scenario. Refer to BCBA® Task List (5th ed.) Section D-5: Use single-subject experimental designs (e.g., reversal, multiple baseline, multielement, changing criterion).Test your ABA Terminology ➠ Derivative Measures Explained Put your knowledge of occurence measurement to the test with PTB co-founder Dana Meller as she discusses the two types of derivative measures, and each of their defining features and applications. Dana focuses on the derivative measure used for comparing two or more procedures, teaching clients new skills, evaluating mastery over a class of concepts, and the various measurement methods. Refer to BCBA® Task List (5th ed.) Section C-6: Measure trials to criterion.Experimental Validity: The Relationship between Behavior Change & Independent Variables PTB co-founder explains the different types of validity in ABA. Refer to BCBA® Task List (5th ed.) Section D-2: Distinguish between internal and external validity.Test your ABA Terminology ➠ Indicators of Trustworthy Measurement Test your knowledge with PTB co-founder Dana Meller as she explains the specific indicator of trustworthy measurement that corresponds with repeated measurement yielding the same result. Included is a description of all three indicators of trustworthy measurement validity, accuracy, and reliability. Refer to BCBA® Task List (5th ed.) Section C-8: Evaluate the validity and reliability of measurement procedures.Breaking Down a Mock BCBA® Exam Question: Understanding Equal-Interval Graphs & Logarithmic Scales Test your knowledge of ABA graphs with PTB co-founder Dana Meller as she reviews a BCBA® mock exam question about equal-interval graphs, exploring their unique properties. Included, Dana explains the concept of proportional values and highlights the graph(s) which operate on a logarithmic scale, offering a different perspective on changes in behavior. Refer to BCBA® Task List (5th ed.) Sections C-10: Graph data to communicate relevant quantitative relations (e.g., equal-interval graphs, bar graphs, cumulative records); C-11: Interpret graphed data.Test your ABA Terminology ➠ Confounding Threats to Internal Validity Test your knowledge of measurement confounds with PTB co-founder Dana Meller as she discusses one of the four types of threats to internal validity, with corresponding examples. Refer to BCBA® Task List (5th ed.) Section C-8: Evaluate the validity and reliability of measurement procedures.Breaking Down a BCBA® Mock Exam Question: It's the IOA Battle Royal. Which Formula Gets Knocked Out? Sharpen your measurement skills with PTB co-founder Dana Meller as she reviews a BCBA® mock exam question about IOA and helps explain the different formulas used for time sampling measurements. Dana covers four IOA formulas: Interval-by-Interval, Scored Interval, Trial-by-Tial, and Unscored Interval; and highlights key considerations and pitfalls associated with each. BCBA® Task List (5th ed.) Section C-8: Evaluate the validity and reliability of measurement procedures.Test your ABA Terminology ➠ Fundamental Properties of Behavior Change Test your ability to interpret graphed data with PTB co-founder Dana Meller. Here she explains the three fundamental properties of behavior change, focusing on one specific property akin to an average or median. Included are descriptions of level, trend, variability, and the y-axis. Refer to BCBA® Task List (5th ed.) Section C-11: Interpret graphed data.Breaking Down a BCBA® Mock Exam Question: The #1 Threat to Accuracy and Reliability Test your measurement knowledge with PTB co-founder Dana Meller as she reviews a BCBA® mock exam question about the key indicators of trustworthy measurement, revealing the most significant threat facing accuracy and reliability. Dana provides insight into the distinctions between reliability, validity, and accuracy and how they relate to measurement. BCBA® Task List (5th ed.) Section C-8: Evaluate the validity and reliability of measurement procedures.Threats to Validity Exposed: When Misleading Data Plays Tricks on Your Perception Test your knowledge of measurement procedures with PTB co-founder Dana Meller as she explains, in detail, one of the threats to validity with several corresponding examples. Dana also shares a clever memorization study tip that will help you on the Big exam. Refer to BCBA® Task List (5th ed.) Section C-8: Evaluate the validity and reliability of measurement procedures. PTB Year in Prep: A Data-Filled Look at 2023’s Study Stats As scientists, we know you love data. PTB crunched the numbers based on behaviors of the thousands of dedicated students who trusted us with their journey to certification. It’s been…Beat the Odds: Factors that Impact Performance on the BCBA® Exam Though the exam may be difficult, it’s not impossible to achieve a passing score. There are several ways students can improve their chances and beat the odds. The right preparation is essential.How Hard is it to Pass the BCBA® Exam? The question every future BCBA® inevitably asks: how hard is it to pass the BCBA® exam? If you’ve heard the stories or seen the data, then you know the exam has a reputation for being difficult. Ask around and you’ll likely hear that it’s sort of like running a marathon. But barefoot, on broken glass, in a giant corn maze, guarded by storm troopers and you can’t remember where you left your lightsaber…oh, and your headphones just died. Dana Do's: What Do Philosophical Assumptions Got To Do With It? It often feels like the board is asking candidates to study concepts you may never use in practice. PTB co-founder Dana Meller explains why that's actually inaccurate. The philosophical assumptions underlying the science of behavior analysis is so much more integral than just passing the big exam.Stuffed Schedule? 6 Tips for Better Time Management #1: Set Deadlines Believe it or not, setting deadlines can help you get more done. Parkinson’s Law is the idea that “work expands to fill the time available for its…5 Science-Backed Tips to Make Your Study Space More Soothing #1 – Declutter to De-stress Fortunately, this first tip costs nothing. Unfortunately, it may require a bit of elbow grease. Organizing your study or work station can help you better…5 Foods to Boost Brainpower While Studying #1 Green tea You’d be hard pressed to find an ABA student who isn’t reaching for caffeine in one form or another. Try sipping on green tea the next time…From PTB’s Test (Prep) Kitchens: A Brain-Boosting Berry Smoothie It’s important to fuel your brain and body with nutritious food that will give you the energy to power through long days and even longer study sessions. But, between school,…Dana Do's: What Chaining Method to Use When? The books don't really say much about what chaining methods BCBA's should apply to what behaviors. PTB co-founder Dana Meller breaks it down. Refer to BCBA® Task List (5th ed.) Section G-8: Use chaining.Behind the Scenes of the Big Exam Prep Workshop Known for her trademark humor and clinical knowledge, PTB co-founder Dana Meller takes students behind the scenes of creating the PTB Streaming Lecture Series, a collection of 9 pre-recorded lectures covering each of the BCBA® 5th edition task list sections.Dana Do's: BCBA® Exam Prep Studying Tips PTB co-founder Dana Meller shares helpful tips about incorporating studying into your already busy lives. Dana Do's: How to Make Time for Studying for the BCBA® Exam PTB co-founder Dana Meller shares helpful tips about incorporating studying into your already busy lives.Dana Do's: The Problem With Making Assumptions on the BCBA® Exam PTB co-founder Dana Meller shares practical insight on the importance of approaching exam questions at face value.Dana Do's: Use Mistakes to Assess How You Test PTB co-founder Dana Meller shares insights on how to use your mock BCBA® exam mistakes to assess and improve your test-taking behavior.
