ISSCM MIDTERM 1 QUESTIONS AND ANSWERS
TRUE/FALSE: Categorical variables can be classified as either discrete or continuous. - CORRECT
ANSWER✅✅False. They are classified as nominal or ordinal
TRUE/FALSE: The histogram shows the strength and direction of relationship between two numerical
variables. - CORRECT ANSWER✅✅False. The scatter plot shows this.
TRUE/FALSE: If two different data sets with the same number of observations have the same mean, then
their medians must also be equal. - CORRECT ANSWER✅✅False. The medians can be different, ex.
1,2,3, mean=2 median=2 0.5,1.5,4 mean:3 median:1.5
TRUE/FALSE: Interquartile range is a measure of central tendency for the data. - CORRECT
ANSWER✅✅False. Interquartile range is a measure of spread.
TRUE/FALSE: A frequency table indicates how many observations fall within each bin, and a histogram is
its graphical analog. - CORRECT ANSWER✅✅True.
TRUE/FALSE: In the term "frequency table," frequency refers to the counts of observations in specified
bins. - CORRECT ANSWER✅✅True.
TRUE/FALSE: A distribution of a numerical variable with no skewness is said to be symmetric. - CORRECT
ANSWER✅✅True.
TRUE/FALSE: Suppose that a sample of 10 observations has a standard deviation of 3. Then the sum of
the squared deviations from the sample mean is 30. - CORRECT ANSWER✅✅False. s=3, s^2=9, by the
formula of variance, s^2(n-1)=9*9=81
TRUE/FALSE: The mode is a measure of central tendency. - CORRECT ANSWER✅✅True.
TRUE/FALSE: Correlation implies causation. - CORRECT ANSWER✅✅False. Correlation does not imply
causation, since there might be confounding variables that affect both X and Y.
TRUE/FALSE: Categorical variables can be classified as either discrete or continuous. - CORRECT
ANSWER✅✅False. They are classified as nominal or ordinal
TRUE/FALSE: The histogram shows the strength and direction of relationship between two numerical
variables. - CORRECT ANSWER✅✅False. The scatter plot shows this.
TRUE/FALSE: If two different data sets with the same number of observations have the same mean, then
their medians must also be equal. - CORRECT ANSWER✅✅False. The medians can be different, ex.
1,2,3, mean=2 median=2 0.5,1.5,4 mean:3 median:1.5
TRUE/FALSE: Interquartile range is a measure of central tendency for the data. - CORRECT
ANSWER✅✅False. Interquartile range is a measure of spread.
TRUE/FALSE: A frequency table indicates how many observations fall within each bin, and a histogram is
its graphical analog. - CORRECT ANSWER✅✅True.
TRUE/FALSE: In the term "frequency table," frequency refers to the counts of observations in specified
bins. - CORRECT ANSWER✅✅True.
TRUE/FALSE: A distribution of a numerical variable with no skewness is said to be symmetric. - CORRECT
ANSWER✅✅True.
TRUE/FALSE: Suppose that a sample of 10 observations has a standard deviation of 3. Then the sum of
the squared deviations from the sample mean is 30. - CORRECT ANSWER✅✅False. s=3, s^2=9, by the
formula of variance, s^2(n-1)=9*9=81
TRUE/FALSE: The mode is a measure of central tendency. - CORRECT ANSWER✅✅True.
TRUE/FALSE: Correlation implies causation. - CORRECT ANSWER✅✅False. Correlation does not imply
causation, since there might be confounding variables that affect both X and Y.
