Business Analytics Exam queries
and answers graded A+
Histogram - ANS✅✅Similar to a bar chart with the bin counts used as the heights of the bars.
Note: there are no gaps between bars unless there are actual gaps in the data.
Bins are usually in multiples of 5 or 10
Stem-and-Leaf Display - ANS✅✅Like histograms, but they also give individual values
Stem is the first number, leaf is the second
Ex) 2|1
Categorical Data cannot be displayed in which graphs? - ANS✅✅Histograms and Stem-and-Leaf
Diagrams
Quantitative Data cannot be displayed in what kind of charts? - ANS✅✅Bar Charts, or Pie Charts
How do you describe the shape of a distribution? - ANS✅✅In terms of its modes, symmetry, and
whether it has any gaps or outlying values.
What are modes? - ANS✅✅Peaks or humps seen in an Histogram
A distribution whose histogram doesn't appear to have any mode and in which all the bars are
approximately the same height is called what? - ANS✅✅Uniform
Tails - ANS✅✅The thinner ends of a distribution
If one tail stretches out farther than the other, the distribution is said to be what? -
ANS✅✅Skewed to the side of the longer tail
Outliers - ANS✅✅Those values that stand off away from the body of the distribution
4 Characteristics of Outliers - ANS✅✅1. Can affect every statistical method we will study.
, 2. Can be the most informative part of your data.
3. May be an error in the data.
4. Should be discussed in any conclusions drawn about the data.
Why is the median said to be resistant? - ANS✅✅Because it isn't affected by unusual observations
or by the shape of the distribution
T/F: The median is resistant to unusual observations and to the shape of the distribution. -
ANS✅✅True
T/F: The mean is NOT resistant to unusual observations and to the shape of the distribution. -
ANS✅✅True
What is the best choice for skewed data? - ANS✅✅Median
Define Range - ANS✅✅Range = Max - Min
Quartiles - ANS✅✅The values that frame the middle 50% of the data
Interquartile Range (IQR) - ANS✅✅Defined as the difference between the two quartile values
IQR = Q3 - Q1
Variance - ANS✅✅The average of the squared deviations of the values of the variable y from the
mean
s² = ∑ (y - y prime)²/ n -1
Standard Deviation - ANS✅✅s = √∑ (y - y prime)²/ n -1
If shape is skewed, what should be reported? - ANS✅✅Median and IQR
If the shape is unimodal and symmetric, - ANS✅✅Mean and Standard Deviation should be
reported, and maybe median and IQR
and answers graded A+
Histogram - ANS✅✅Similar to a bar chart with the bin counts used as the heights of the bars.
Note: there are no gaps between bars unless there are actual gaps in the data.
Bins are usually in multiples of 5 or 10
Stem-and-Leaf Display - ANS✅✅Like histograms, but they also give individual values
Stem is the first number, leaf is the second
Ex) 2|1
Categorical Data cannot be displayed in which graphs? - ANS✅✅Histograms and Stem-and-Leaf
Diagrams
Quantitative Data cannot be displayed in what kind of charts? - ANS✅✅Bar Charts, or Pie Charts
How do you describe the shape of a distribution? - ANS✅✅In terms of its modes, symmetry, and
whether it has any gaps or outlying values.
What are modes? - ANS✅✅Peaks or humps seen in an Histogram
A distribution whose histogram doesn't appear to have any mode and in which all the bars are
approximately the same height is called what? - ANS✅✅Uniform
Tails - ANS✅✅The thinner ends of a distribution
If one tail stretches out farther than the other, the distribution is said to be what? -
ANS✅✅Skewed to the side of the longer tail
Outliers - ANS✅✅Those values that stand off away from the body of the distribution
4 Characteristics of Outliers - ANS✅✅1. Can affect every statistical method we will study.
, 2. Can be the most informative part of your data.
3. May be an error in the data.
4. Should be discussed in any conclusions drawn about the data.
Why is the median said to be resistant? - ANS✅✅Because it isn't affected by unusual observations
or by the shape of the distribution
T/F: The median is resistant to unusual observations and to the shape of the distribution. -
ANS✅✅True
T/F: The mean is NOT resistant to unusual observations and to the shape of the distribution. -
ANS✅✅True
What is the best choice for skewed data? - ANS✅✅Median
Define Range - ANS✅✅Range = Max - Min
Quartiles - ANS✅✅The values that frame the middle 50% of the data
Interquartile Range (IQR) - ANS✅✅Defined as the difference between the two quartile values
IQR = Q3 - Q1
Variance - ANS✅✅The average of the squared deviations of the values of the variable y from the
mean
s² = ∑ (y - y prime)²/ n -1
Standard Deviation - ANS✅✅s = √∑ (y - y prime)²/ n -1
If shape is skewed, what should be reported? - ANS✅✅Median and IQR
If the shape is unimodal and symmetric, - ANS✅✅Mean and Standard Deviation should be
reported, and maybe median and IQR
