C207 Study Session Guide 2024/25 EDITION GUARANTEED GRADE A+

Analytics is the discovery, analysis and communication of meaningful patterns in data Information Bias A prejudice in the data that results when either the respondent or the interviewer has an agenda that affects responses Ordinal Data places data into categories that are ordered by a predetermined criteria Omission Error occurs when something (for example data or survey response) is missing Interval Data is numerical data that is ordered, is equal distance apart and does not have a natural zero Reliable Data is consistent and repeatable. Random Error represents errors in data caused by unpredictable statistical fluctuations Nominal Data places data into "either or" categories or identifies by name or characteristic Data Management includes cleaning and storage of collected data. Big Data is a massive amount of data that is difficult to process using traditional database and software techniques Ratio Data is numerical data that has a natural zero allowing this data to be added, subtracted, multiplied and divided. Measurement Bias is a prejudice in data that results when the sample is not representative of the population be tested Why is quantitative analysis and analytics important in decision making? (Choose 3) Decisions are less subjective, Analytics can be explanatory and Managers can build predictive models determine whether it's an example of Descriptive, Predictive, or Prescriptive Analysis: Sales for the Northern Region are expected to decrease 2% in the next fiscal year Predictive Analysis determine whether it's an example of Descriptive, Predictive, or Prescriptive Analysis: The median household income for New York City from is $58,003 Descriptive Analysis determine whether it's an example of Descriptive, Predictive, or Prescriptive Analysis: Alternating two trains between 5:00 p.m. and 7:00 p.m. will increase on time arrivals. Prescriptive Analysis determine whether it's an example of Descriptive, Predictive, or Prescriptive Analysis: The largest consumer group of the product is female Descriptive Analysis determine whether it's an example of Descriptive, Predictive, or Prescriptive Analysis: Employee turnover for the organization will be more than 5% Predictive Analysis determine whether it's an example of Descriptive, Predictive, or Prescriptive Analysis:. Increasing the ratio of ingredient A to ingredient B to 1:1.5 will yield more product Prescriptive Analysis Stage 1 of the Davenport-Kim Three-stage Model includes which two of the following steps Review of previous findings and Problem recognition Stage 2 of the Davenport-Kim Three-stage Model includes which two of the following steps? Solve the problem and Data collection Which data type is types of cars produced in a factory? Nominal Which data type is distance between each process step measured in inches? Ratio Which data type is the age group of survey participants? Ordinal What type of data is a pain scale (example: 1 - 10)? Interval What type of data is the age of each participant in a survey? Ratio Select the elements of an Experimental Study: (Choose 3) Responses, Treatments, Experimental Units This bias occurs if the sample is not randomized. Measurement . When an instrument produces a consistent output it is Reliable This type of error will cancel itself out over a large number of measurements Random A study in which the use of a placebo is known by the treatment allocator or researcher but not by the participant is considered a(n): Blind Study Cleaning and storing collected data is: Data Management Which of the following statistics are unaffected by a single large outlier? (More than one) Median, Interquartile range (IQR) and Mode Which of the following is most suitable for policy making based on income distribution? Mean, Median or Standard deviation Median Because of assumed skewed distribution If we study data from a population whose mean is 200 and standard deviation is 30, which of the following data points has a z-score of -3? 110 ( =110) Which of the following statistics measures the spread of the dataset away from mean? (More than 1) Interquartile Range(IQR), z-score, range, variance Interquartile Range(IQR), range and variance An experiment consists of rolling a die and flipping a coin. Which two choices below best apply for computing the probability of rolling a 6 on a die AND flipping head on a coin? Multiplication and Intersection (Keyword = AND) An experiment consists of rolling a die and flipping a coin. Which two choices below best apply for computing the probability of rolling a 6 on a die OR flipping head on a coin? Addition and Union (keyword = OR) The probability that a baby is a girl, given that the baby is wearing pink is 0.8. The probability that a baby is a girl is 0.5. Which of the choices below best applies for determining the probability that a baby is wearing pink GIVEN THAT the baby is a girl? Bayes (Keyword = GIVEN THAT) A government official noticed that the Total US Highway Fatality Rate was strongly correlated to the tons of lemons imported. Before concluding that the more lemons we import the lower the fatality rate, what is the main issue should the official think about here? Is there a causal relationship? Is the correlation strong enough? What is the slope of the regression line? Is there a causal relationship? (Correlation doesn't equal causation) For the scatter diagram below, which of the following describes the correlation? Strong Negative, Strong Positive, Weak Negative, Weak Positive Strong Negative We examine a population with normal distribution having a mean = 1,000 and standard deviation = 50. What approximate percentage of the population lies between 850 and 1150? 68%, 95%, 99.7%, 100% 99.7% (z-score for 850 = (850-1000)/50 = -150/50 = -3 z-score for 1150 = ()/50 = +150/50 = +3) We examine a population with normal distribution having a mean = 1,000 and standard deviation = 50. What approximate percentage of the population lies between 900 and 1100? 68%, 95%, 99.7%, 100% 95% (z-score for 900 = (900-1000)/50 = -100/50 = -2 z-score for 1100 = ()/50 = +100/50 = +2) We examine a population with normal distribution having a mean = 1,000 and standard deviation = 50. What approximate percentage of the population lies between 950 and 1050? 68%, 95%, 99.7%, 100% 68% (z-score for 950 = (950-1000)/50 = -50/50 = -1 z-score for 1050 = ()/50 = +50/50 = +1) How are Z-scores from a population with a normal distribution distributed? Normal Distribution with mean = 0 and standard deviation = 1, Normal Distribution with the same mean and standard deviation, Need more information Normal Distribution with mean = 0 and standard deviation = 1 If we need to examine the relationship between age and salary, which of the following would be most useful? Scatter plot (Keyword = Relationship) Consider a population with mean 100 and standard deviation of 10. If we randomly select a data point from the population, what is the probability that the point will be between 90 and 110? (Hint: consider the Z-scores)? 68%, 95%, 99.7%, 100% 68% (z-score for 90 = (90-100)/10 = -10/10 = -1 z-score for 1050 = (110-100)/10 = +10/10 = +1) A gym owner wants to now the TYPICAL time a patron spends at the gym. Which is the best statistic to consider? Mean, Mode, Range, Variance Mode (Keyword = TYPICAL) This misuse of statistics occurs when the respondents to a survey say what they believe the questioner wants to hear. (Confirmation bias, Response bias, Conscious bias, Systematic bias Response Bias This misuse of statistics occurs when the surveyor is actively seeking a certain response to support his or her theory or cause. Bias can occur when the researcher manipulates the phrasing of questions in order to elicit the desired response. Confirmation, Response, Conscious, Systematic bias Conscious bias For the box plots above, which experiment has the lowest median? Experiment No 1, 2, 3, 4, 5 Experiment No 3 For the box plots above, excluding outliers, which experiment has the lowest data point? Experiment No 1, 2, 3, 4, 5 Experiment No 4 _________________is a general direction in which something is developing or changing trend _________________verifies if multiple populations of data are the same or at least one is different than the others. ANOVA (analysis of variance) We have an expert-written solution to this problem! . _________________describes results that go up and down periodically, but don't necessarily follow the calendar cyclicality _________________assumes that the variance of a dependent variable is consistent across the range of values homoscedasticity . _________________is the midpoint value of a group of measurements median . _________________is a group of observations that have something in common Statistical population _________________is the average of a group of measurements mean . _________________is the assumption that the variance of a dependent variable changes across the range of values heteroscedasticity _________________is calculated from (responses to) the value of the other variables in an equation dependent variable _________________occurs when there is a one-time unusual measurement in a process irregularity _________________describes variability in a process that occurs at the same time of year each year seasonality . _________________in a time series regression, describes events whose probability of occurring depends upon the events that occurred previously autocorrelation _________________describes the variability that occurs in events for which we have no explanation random variation _________________is a variable in an equation to which we can assign a specific value and predict the value of another variable. independent variable . _________________is a measurement that is very different than other measurements of similar events Outlier . _________________is the most common or typical measurement of a group of events Mode Linear Programming (optimization) finds a maximum or minimum solution in a situation that has various constraints (T/F) True If we are analyzing which among three equipment options for a new office would be the best choice, we might use Crossover Analysis (T/F) True In a Crossover Analysis considering three options, every crossover point is essential to our analysis (T/F) False Break-even Analysis requires only fixed and variable cost information (T/F) False (Needs fixed cost, variable cost & Revenue) The Mean can be found on the left, middle or right portions of a Normal Curve (T/F) False (Mean of normal curve is in the middle) The Average and the Mean are synonyms (T/F) True ANOVA (Analysis of Variance) helps us determine statistical differences between groups of data (T/F) True The Z-test is the key statistic for an ANOVA analysis (T/F) False (F stat) Regression Analysis creates a "Best Fit" line for a set of data (T/F) True Time Series Analysis requires finding the best experts who will predict what is coming in the future (T/F) False Cluster Analysis is used to find groupings in a set of data (T/F) True Decision Analysis uses a weighted average of all possible outcomes to determine the best course of action (T/F) True The Independent Variable is the prediction that is calculated from the data of a specific situation (T/F) False The Correlation of a set of data reveals what is causing the pattern we are seeing (T/F) False (Correlation is not causation) Error Measurements help determine which forecasting tool is most useful for predicting future events (T/F) True Least Squares and Linear Regression are synonyms (T/F) True Cyclicality refers to patterns that return each January (T/F) False A general increase in sales over time is considered a Trend (T/F) True Multiple Linear Regression has more than one Independent Variable (T/F)