MISY 262 Exam 1 questions with 100% correct answers 2023/2024

MISY 262 Exam 1 Variable - correct answer Anything that can be measured and can vary across entities or time Discrete variable - correct answer Can only take certain values Categorical variable - correct answer Discrete; can only take on distinct category values Binary variable - correct answer Discrete; categorical; can only take on two categories i.e. Yes or No Nominal variable - correct answer Discrete; categorical; but with no numerical values associated Ordinal variable - correct answer Discrete; categorical; nominal; but with logical order Continuous variable - correct answer Can take on any value in an interval i.e. (-1,3) Frequency Distribution - correct answer Also called a histogram; graph plotting values of observations on the horizontal axis and the count of how many times each value appears on the vertical axis Measures frequency of observation variables Helps us assess distributional qualities of a random variable Standard Deviation - correct answer Mean distance of the observations from their mean (x-mean of sample)^2 / how many numbers in the sample - 1 Variance - correct answer Square of standard deviation Denoted by s^2 Outliers - correct answer Unusual observations that lie away from the bulk of the data Removing them can help improve a model's fit to the remaining data Identify visually through frequency distribution or Interquartile range Interquartile Range - correct answer If observation is below Q1 + 1.5 * (Q3-Q1) or above Q3 + 1.5 * (Q3-Q1) Then the data might be an outlier Population - correct answer The set of all measurements corresponding to each unit of the entire population of units about which information is sought Sample - correct answer A subset of measurements from a population that are collected in the course of an investigation Random Sample - correct answer Each subject in the population is equally likely to be chosen Scatterplot - correct answer Illustrates the relationship between two variables using dots Covariance - correct answer Measure of how observations of two random variables vary together Positive Relationship - correct answer Positive value of covariance As one variable increases, so does the other