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WGU C207 STUDY GUIDE 2026 MASTER
SOLUTION DIGEST
◉Accurately measures what it is intended to measure Answer: Valid data ◉________ an experimental study prevents bias. Answer: Blinding ◉Neither the treatment allocator nor the participant knows in which group the participant is contributing. (Who is getting the real drug?) Answer: Double blind study ◉The participants are not told if they are in the treatment group or control group Answer: Blind study ◉Describes characteristics of a dataset. Mean, median, mode, variation, standard deviation, range.... Answer: Descriptive analytics ◉Uses data from t he past to predict the future Answer: Predictive ◉Uses experimental design and optimization to predict a future Answer: Prescriptive
◉If we move to six appointments an hour we can increase revenue 2%. Which form of analytics is this? Answer: Prescriptive - We are taking a specific course of action ◉Based on the last four quarters, we can predict $4,1 million in sales next quarter. Which form of analytics is this? Answer: Predictive: We aren't taking any action ◉The number of appointments per day averaged 7 over the last 6 months. Which form of analytics is this? Answer: Descriptive: We are only describing the past. No future predictions are made. ◉Is Big Data structured, unstructured or both? Answer: Both ◉Where do we store big data Answer: In a big data warehouse ◉Why do marketing teams use big data? Answer: "Datamining" assists in targeting the best customers for new products or reaching existing customers for like products ◉Name the 4 levels of measurement Answer: (NOIR) Nominal, Ordinal, Interval Ratio
◉If a sample is not random it creates ____________ Answer: Measurement Bias ◉If a sample is not the right size it creates ___________ Answer: Measurement Bias ◉Measuring the housing market in North Carolina when making an inference about the entire East coast is an example of __________ Answer: Non-representative Sample ◉Lemonade sales increase when it is warmer than 75 degrees. Weather and lemonade are __________ Answer: Correlated. "NOT CAUSE" ◉Pulling names from a hat is a tool to create a ______ sample Answer: Random ◉Asking participants to taste test a yellow candy and a blue candy and select one can create bias. How can we prevent bias? Answer: Blinding ◉You are taking a survey and the question is leading. It seams advantageous to answer a specific way. What type of bias is this? Answer: Conscious KEYWORD: Benefit
◉A question is not leading, but you feel your boss might want you to answer a specific way Answer: Response You feel there is an "expected" response and may not answer honestly (no leading ) ◉pread of the data Answer: Standard Deviation A normally distributed sample spreads from - 3 to +3 standard deviations from the mean ◉We should not use this measure of central tendency alone for decisions because it includes outliers Answer: Mean ◉The best measure of central tendency when making decisions Answer: Median ◉We use this measure of central tendency if we want to know what happens the most Answer: Mode (most can also be defined as typical or common) ◉If the mean is 50 and the standard deviation is 5, what is the probability of being between 45 and 55? Answer: 68.2% (of the sample will be within 1 standard deviation of the mean) 50 - 5 = 45 and 50 + 5 + =
◉You want to know how your height compares to all of your family tree. How do you calculate a z score? Answer: (Your height - the mean of the family tree height) divided by the standard deviation of the family tree height (me-mean)/standard deviaiton ◉You are 63" tall and the family tree averages 67" with a standard deviation of 2". What is your z-score? Answer: (63-67)/2 = - 2 You are 2 standard deviations shorter than the family tree. ◉Which measure lets you measure your height compared to your maternal family tree and your height compared to your paternal family tree? Answer: z-scores let us measure two samples by putting them to the same scale. ◉There are four shopping carts available and one has a broken wheel. What is your probability of selecting the cart with the broken wheel? Answer: 25% (1/4 = 0.25) ◉There is a 20% of parking close to the door and a 30% chance of getting the shopping cart with a squeaky wheel. How do we calculated the probability of both events occurring? Answer: Multiply Key Words: AND, ALL, BOTH ◉There is a 20% of parking close to the door and a 30% chance of getting the shopping cart with a squeaky wheel. How do we
calculated the probability of either event occurring? Answer: Addition Key Words: OR, EITHER ◉Multiplying two events calculates an ____________ Answer: Intersection ◉Adding two events calculates a _______________ Answer: Union ◉The grocer is running a 10 for $10 special on cans of soup. You can mix and match the 5 different flavors of soup. You decide to purchase 10 cans. What can we use to count all the possible outcomes of flavors picked? Answer: Combination ◉There is a 90% chance you will have to wait in line for more than 6 minutes to check out at the grocer. What is the complement? Answer: 10%. If there is a 90% chance of yes, then there is a 10% chance of no. 90% + 10% = 100% ◉50% chance it will rain. There is a 20% chance you park in the garage in the rain and a 60% chance you park there if it is not raining. Given you are parked in the garage, what is the probability it is raining? Which probability technique applies? Answer: Bayes ◉You conduct a quick survey asking friends to rate your new website on a scale of 1 - 10. Which graph will show how the
◉You want to compare the average daily gas prices in your neighborhood to average daily gas prices by the Interstate. Name your tool. Answer: Two Sample t-test ◉You want to compare the average weekly gas prices in your neighborhood to your annual budgeted price. Name your tool. Answer: One Sample t-test ◉T-test uses this test statistic Answer: T-stat. (must be higher than critical value to reject the null) ◉ANOVA uses this test statistic Answer: F-stat. (must be higher than critical value to reject the null) ◉You want to compare price per gallon between the neighborhood gas station, the Grocer station and the Interstate station. Name your tool. Answer: ANOVA ◉You want to compare the number of times the price per gallon at your neighborhood station and the Grocer station exceeds the budget price. Name your tool. Answer: Chi-square. The # of times is a frequency, not an average. This is nominal data. ◉_________takes information from one data set and can predict information for another data set. Answer: Regression
◉There is no significant difference in the price per gallon between Station #1 and Station #2. Which hypothesis am I? Answer: Null Null is always "no" ◉Your p-value is 0.04. Can you reject the null? Answer: Yes. LESS then 0.05 means YES. when interpreting the p-value. ◉Your t-stat is 2.06 and your t-critical is 1.65. Can you reject the null? Answer: Yes. If your score (t-stat) is larger than your cut score (t-critical), you pass the test! ◉Your F-stat is 0.26 and you F-critical is 1.96. Can you reject the null? Answer: No. If your score (F-stat) is smaller than your cut score (F-critical), you do not pass the test. We can only Reject when we pass. ◉Your reject the null hypothesis. Did you find significance? Answer: Yes. Rejecting the null ("no") means we found something statistically significant. Yay! ◉The process of arranging terms or values based on different variables into "natural" groups Answer: Cluster Analysis
◉Disadvantage of _____ Analysis: Assumes past data patterns will repeat in future, which may not be true Answer: Time Series ◉Advantage of ___ Analysis: Helps determine target markets Answer: Cluster Analysis ◉Advantage of ____ Analysis: Allows sophisticated analysis of cost behavior and sales forecasts Answer: Regression Analysis ◉Regression determines the Answer: relationship between two data sets ◉Goodness of fit is defined by Answer: R-squared How much of the dependent variable can be determined by the independent variable? ◉The p-value of your regression analysis comes out to be 0.62. Is the independent variable a significant predictor of the dependent variable? Can we reject the null? Answer: No. LESS than 0.05 means Yes. 0.62 is higher than 0.05. No significance. ◉The R-squared value is 0.71. Is this a strong goodness of fit? Answer: Yes. On a scale of 0% - 100%, 71% is a strong fit. 71% of the dependent is made up from the independent.
◉We wish to determine if the minutes student spend taking a test can predict their test score. In this scenario, which is the independent variable? Answer: Minutes spend taking the test. ◉As a new manager, you analyze the number of clicks into your website each subscriber makes in a month to determine how much they spend. In this scenario, spending is which variable? Answer: Dependent. The dependent is always what we are trying to predict. ◉Can correlation be a negative number? Answer: Yes. ◉True or False: - 0.99 is a stronger relationship than 0.74 Answer: TRUE ◉Linear regression is often referred to as Answer: Ordinary Least Squares (OLS) Regression ◉y = 10x + 50. Solve for y if x = 10 Answer: y = 10(10) + 50 y = 150 ◉Our regression module for number of clicks predicting spending on our website is y = 6 + 5x. If a subscriber has 4 clicks, how much will they spend? Answer: y = 6 + 5(4) y = 26
◉We use the amount of snow fall in inches monthly and the employee's previous call off rates to predict call offs next month. Which regression is this? Answer: Multiple. We have more than one independent variable. ◉We use the amount of snow fall in inches monthly and the employee's previous call off rates to predict call offs next month. This analysis can be affected by ______. Answer: Autocorrelation. Whenever time is an independent variable, you can may this. ◉y = 50 + 20x1 - 10x2. If x1 = 2 and x2 = 6, solve for y. Answer: y = 50 + 20(2) - 10(6) y = 50 + 40 - 60 y = 30 ◉States that a company is dedicated to quality practices and is continually working to ensure that it is producing at the highest level possible. (Global Standards) Answer: ISO: International Organization for Standardization ◉After several trials we decide to implement our new procedure to eliminate quality defects. Which stage of PDCA are we in? Answer: Act (trialing is doing, after trial success we act) ◉We measure the effectiveness of our trial of a new procedure. Which phase of the PDCA are we in? Answer: Check
◉Focus on eliminating anything that does not add value to customers or satisfy the customers' need Answer: Lean ◉Name the quality principle: understand customers' current and future needs and strive to meet or exceed those needs Answer: A focus on customers ◉Name the quality principle: People at all levels of the organization must be fully engaged and involved in the pursuit of quality to maximize its benefits to the organization Answer: Engaged Colleagues ◉Name the quality principle: ensure consistency and efficiency among organization-wide activities Answer: Systems Approach ◉Name the quality principle: These informed decisions reduce bias and foster trust in decisions and plans Answer: Fact-based decisions ◉Prevent defects from occurring Answer: Quality Assurance ◉Assess performance and recommend corrective action Answer: Quality Control ◉Training Answer: Quality Assurance
◉Data allows you to evaluate information as part of a range rather than as an absolute—results can be rated on a scale (at any point between 0 and infinity, including decimals). Answer: Variable ◉What types of variation will a control chart display? Answer: Special cause and Common cause variation ◉Ishikawa claimed that these seven tools could be used to solve __________ of the quality-related problems organizations see Answer: 90% - 95% ◉Graphic representations of data that help teams address problems Answer: Seven basic tools of quality ◉Used to illustrate performance measurements over a period of time Answer: Run chart Keyword: Over Time ◉Name two quality tools to identify process problems Answer: Flow Chart (Where) and Cause and Effect Diagram (Why) ◉Graphic representation of the steps that make up a process Answer: Flowchart
◉This tool is an easy way to collect and tabulate data Answer: Check sheet ◉Quality tools used to graphically display distribution Answer: Histogram and Pareto Chart ◉Measures how continuous data is distributed over various ranges Answer: Histogram ◉Used to show categories in highest to lowest order Answer: Pareto Chart ◉Displays a relationship between two variables Answer: Scatter diagram ◉Methodology that works to eliminate variation and increase the capability of processes to meet requirements successfully Answer: Six-Sigma ◉Waste is removed from all of the activities in a process Answer: Lean ◉Contain all of the steps, processes, and communication involved in the production of goods or services Answer: Value Stream
