BUAL 2600 GRAMLING EXAMS SCRIPT UPDATED
QUESTIONS AND ANSWERS SURE A+
✔✔Variance - ✔✔The average of the squared deviations of all the population
measurements from the population mean
✔✔Standard Deviation - ✔✔The square root of the population variance; How spread out
the data
✔✔Standard Deviation Notation - ✔✔-The standard deviation tells us how SPREAD
OUT from the mean THE DATAPOINTS are in the dataset
-Population standard deviation notation is σ(sigma)
-Sample standard deviation notation: s
✔✔68% - 95% ‐99.7% Rule - ✔✔-In a normal curve 68.26% of the observations fall
within 1 standard deviation of the mean. 9
-5.44% of the observations fall within 2 standard deviations of the mean.
-99.73% of the observations fall within 3 standard deviations of the mean.
✔✔Z-Scores - ✔✔is the number of standard deviations that the raw score, x, is from the
mean
, ✔✔A positive z score - ✔✔tells us raw score is # standard deviations above (greater
than) the mean
✔✔A negative z score - ✔✔tells us raw score is # standard deviations below (less than)
the mean
✔✔Percent - ✔✔Part of the whole from pie graphs using relative frequencies
✔✔Percentile - ✔✔is a measure that tells us what percent of the total frequency scored
at or below that measure. A percentile rank is the percentage of scores that fall at or
below a given score.
✔✔Mean>Median - ✔✔Right skewed
✔✔Mean < Median - ✔✔Left Skewed
✔✔Mean = Median - ✔✔Normal or Symetrical
✔✔What is the 5 number summary? - ✔✔Q1,Q2,Q3,Max, & Min
✔✔Does the order you list the 5 number summary in matter? - ✔✔No
✔✔N(_____,____) - ✔✔N(Mean, Standard Deviation)
✔✔What does Z tell you? - ✔✔the number of standard deviations above or below the
mean
✔✔How do you find the Range? - ✔✔Max - Min
✔✔When do you use range? - ✔✔When data is normal
✔✔How do you find the Z-Score? - ✔✔Z= (x-mean)/ standard deviation
✔✔How do you find the standard dievation? - ✔✔Standard Deviation = √Variance
(square root of variance)
✔✔What graphs are used to show qualitative data? - ✔✔-Bar Graph
-Pie Chart
-Pareto Chart
✔✔What graphs are used to show quantitative data? - ✔✔-Histogram
-Scatterplot
QUESTIONS AND ANSWERS SURE A+
✔✔Variance - ✔✔The average of the squared deviations of all the population
measurements from the population mean
✔✔Standard Deviation - ✔✔The square root of the population variance; How spread out
the data
✔✔Standard Deviation Notation - ✔✔-The standard deviation tells us how SPREAD
OUT from the mean THE DATAPOINTS are in the dataset
-Population standard deviation notation is σ(sigma)
-Sample standard deviation notation: s
✔✔68% - 95% ‐99.7% Rule - ✔✔-In a normal curve 68.26% of the observations fall
within 1 standard deviation of the mean. 9
-5.44% of the observations fall within 2 standard deviations of the mean.
-99.73% of the observations fall within 3 standard deviations of the mean.
✔✔Z-Scores - ✔✔is the number of standard deviations that the raw score, x, is from the
mean
, ✔✔A positive z score - ✔✔tells us raw score is # standard deviations above (greater
than) the mean
✔✔A negative z score - ✔✔tells us raw score is # standard deviations below (less than)
the mean
✔✔Percent - ✔✔Part of the whole from pie graphs using relative frequencies
✔✔Percentile - ✔✔is a measure that tells us what percent of the total frequency scored
at or below that measure. A percentile rank is the percentage of scores that fall at or
below a given score.
✔✔Mean>Median - ✔✔Right skewed
✔✔Mean < Median - ✔✔Left Skewed
✔✔Mean = Median - ✔✔Normal or Symetrical
✔✔What is the 5 number summary? - ✔✔Q1,Q2,Q3,Max, & Min
✔✔Does the order you list the 5 number summary in matter? - ✔✔No
✔✔N(_____,____) - ✔✔N(Mean, Standard Deviation)
✔✔What does Z tell you? - ✔✔the number of standard deviations above or below the
mean
✔✔How do you find the Range? - ✔✔Max - Min
✔✔When do you use range? - ✔✔When data is normal
✔✔How do you find the Z-Score? - ✔✔Z= (x-mean)/ standard deviation
✔✔How do you find the standard dievation? - ✔✔Standard Deviation = √Variance
(square root of variance)
✔✔What graphs are used to show qualitative data? - ✔✔-Bar Graph
-Pie Chart
-Pareto Chart
✔✔What graphs are used to show quantitative data? - ✔✔-Histogram
-Scatterplot
