AP STATISTICS UNIT 5 PROGRESS CHECK MCQ PART 100 PERCENT
CORRECT QUESTIONS AND ANSWERS
◉ If a graph is skewed, should we calculate the median or the mean?
Why? Answer: median; it is resistant to skews and outliers
◉ If a graph is roughly symmetrical, should we calculate the median
or the mean? Why? Answer: mean; generally is more accurate if the
data has no outliers
◉ What is in the five number summary? Answer: Minimum, Q1,
Median, Q3, Maximum
◉ Relationship between variance and standard deviation? Answer:
variance=(standard deviation)^2
◉ variance definition Answer: the variance is roughly the average of
the squared differences between each observation and the mean
◉ standard deviation Answer: the standard deviation is the square
root of the variance
,◉ What should we use to measure spread if the median was
calculated? Answer: IQR
◉ What should we use to measure spread if the mean was
calculated? Answer: standard deviation
◉ What is the IQR? How much of the data does it represent?
Answer: Q3-Q1; 50%
◉ How do you calculate standard deviation? Answer: 1. Type data
into L1
2. Find mean with 1 Variable Stats
3. Turn L2 into (L1-mean)
4. Turn L3 into (L2)^2
5. Go to 2nd STAT over to MATH, select sum(
6. Type in L3
7. multiply it by (1/n-1)
8. Square root it
◉ What is the formula for standard deviation? Answer:
, ◉ Categorical variables vs. Quantitative Variables Answer:
Categorical: individuals can be assigned to one of several groups or
categories
Quantitative: takes numberical values
◉ If a possible outlier is on the fence, is it an outlier? Answer: No
◉ Things to include when describing a distribution Answer: Center
(Mean or Median), Unusual Gaps or Outliers, Spread (Standard
Deviation or IQR), Shape (Roughly Symmetric, slightly/heavily
skewed left or right, bimodal, range)
◉ Explain how to standardize a variable. What is the purpose of
standardizing a variable? Answer: Subtract the distribution mean
and then divide by standard deviation. Tells us how many standard
deviations from the mean an observation falls, and in what direction.
◉ What effect does standardizing the values have on the
distribution? Answer: shape would be the same as the original
distribution, the mean would become 0, the standard deviation
would become 1
◉ What is a density curve? Answer: a curve that (a) is on or above
the horizontal axis, and (b) has exactly an area of 1
CORRECT QUESTIONS AND ANSWERS
◉ If a graph is skewed, should we calculate the median or the mean?
Why? Answer: median; it is resistant to skews and outliers
◉ If a graph is roughly symmetrical, should we calculate the median
or the mean? Why? Answer: mean; generally is more accurate if the
data has no outliers
◉ What is in the five number summary? Answer: Minimum, Q1,
Median, Q3, Maximum
◉ Relationship between variance and standard deviation? Answer:
variance=(standard deviation)^2
◉ variance definition Answer: the variance is roughly the average of
the squared differences between each observation and the mean
◉ standard deviation Answer: the standard deviation is the square
root of the variance
,◉ What should we use to measure spread if the median was
calculated? Answer: IQR
◉ What should we use to measure spread if the mean was
calculated? Answer: standard deviation
◉ What is the IQR? How much of the data does it represent?
Answer: Q3-Q1; 50%
◉ How do you calculate standard deviation? Answer: 1. Type data
into L1
2. Find mean with 1 Variable Stats
3. Turn L2 into (L1-mean)
4. Turn L3 into (L2)^2
5. Go to 2nd STAT over to MATH, select sum(
6. Type in L3
7. multiply it by (1/n-1)
8. Square root it
◉ What is the formula for standard deviation? Answer:
, ◉ Categorical variables vs. Quantitative Variables Answer:
Categorical: individuals can be assigned to one of several groups or
categories
Quantitative: takes numberical values
◉ If a possible outlier is on the fence, is it an outlier? Answer: No
◉ Things to include when describing a distribution Answer: Center
(Mean or Median), Unusual Gaps or Outliers, Spread (Standard
Deviation or IQR), Shape (Roughly Symmetric, slightly/heavily
skewed left or right, bimodal, range)
◉ Explain how to standardize a variable. What is the purpose of
standardizing a variable? Answer: Subtract the distribution mean
and then divide by standard deviation. Tells us how many standard
deviations from the mean an observation falls, and in what direction.
◉ What effect does standardizing the values have on the
distribution? Answer: shape would be the same as the original
distribution, the mean would become 0, the standard deviation
would become 1
◉ What is a density curve? Answer: a curve that (a) is on or above
the horizontal axis, and (b) has exactly an area of 1
