EXST 2201-Exam 1 UPDATED
QUESTIONS AND CORRECT ANSWERS
Statistics - CORRECT ANSWER -The science of collecting, organizing and summarizing, and
analyzing information in order to draw conclusions
-Also, the study of data
Sampling can be done... - CORRECT ANSWER With or without replacement
Benefits of Simple Random Sampling - CORRECT ANSWER -DOES remove selection bias
from sample
-DOES NOT affect the natural variability of data
-DOES NOT guarantee a representative sample
Quantitative Data - CORRECT ANSWER -Data that are numerical and allow the use of
arithmetic operations
-discreet and continuous data
Observational Study - CORRECT ANSWER -A study that measures a characteristic in a
sample WITHOUT controlling the experimental units or the treatment
-Ex post study (after the fact) because the value of the characteristic had already been established
-Can determine association but not causation
-Ex. Height of students in a class
Experimental Design - CORRECT ANSWER -A study that measures a characteristic in a
sample WITH controlling the experimental units or the treatment
-Ex. Weight gain of three females v. males while on high protein diet for one week
Response Variable - CORRECT ANSWER -A quantitative or qualitative variable that reflects
the characteristic of interest
, Relative Frequency - CORRECT ANSWER -The percent, or proportion, of data in each
category
-Frequency/sum of all frequencies
Cumulative Frequency - CORRECT ANSWER -The sum of frequency up through, and
including, the category of interest
-The number of observations less than or equal to the category value
Histogram - CORRECT ANSWER -A graph of a set of data made the same way as a bar chart
except
-The rectangles DO touch
-The value of each class is marked at the middle of each rectangle
Histogram (Continuous Data) - CORRECT ANSWER -A graph of a set of data made the same
way as a bar chart except:
-The rectangles DO touch
-The value of each class is marked at the left side of each rectangle
Stem-and-Leaf Plot - CORRECT ANSWER -A graph to summarize continuous data by
dividing each data point into a stem part and a leaf part and listing these parts
-Is a histogram turned sideways with the data values listed instead of bars to show frequency
Skewed Right - CORRECT ANSWER -The tail of the chart is on the right side of the peak
Skewed Left - CORRECT ANSWER -The tail of the chart is on the left side of the peak
Bimodial - CORRECT ANSWER -Histogram has two peaks
Uniform - CORRECT ANSWER -Every bar on histogram is pretty much the same height
Summary Numbers - CORRECT ANSWER -A numerical quantity used to describe (or
summarize) data
QUESTIONS AND CORRECT ANSWERS
Statistics - CORRECT ANSWER -The science of collecting, organizing and summarizing, and
analyzing information in order to draw conclusions
-Also, the study of data
Sampling can be done... - CORRECT ANSWER With or without replacement
Benefits of Simple Random Sampling - CORRECT ANSWER -DOES remove selection bias
from sample
-DOES NOT affect the natural variability of data
-DOES NOT guarantee a representative sample
Quantitative Data - CORRECT ANSWER -Data that are numerical and allow the use of
arithmetic operations
-discreet and continuous data
Observational Study - CORRECT ANSWER -A study that measures a characteristic in a
sample WITHOUT controlling the experimental units or the treatment
-Ex post study (after the fact) because the value of the characteristic had already been established
-Can determine association but not causation
-Ex. Height of students in a class
Experimental Design - CORRECT ANSWER -A study that measures a characteristic in a
sample WITH controlling the experimental units or the treatment
-Ex. Weight gain of three females v. males while on high protein diet for one week
Response Variable - CORRECT ANSWER -A quantitative or qualitative variable that reflects
the characteristic of interest
, Relative Frequency - CORRECT ANSWER -The percent, or proportion, of data in each
category
-Frequency/sum of all frequencies
Cumulative Frequency - CORRECT ANSWER -The sum of frequency up through, and
including, the category of interest
-The number of observations less than or equal to the category value
Histogram - CORRECT ANSWER -A graph of a set of data made the same way as a bar chart
except
-The rectangles DO touch
-The value of each class is marked at the middle of each rectangle
Histogram (Continuous Data) - CORRECT ANSWER -A graph of a set of data made the same
way as a bar chart except:
-The rectangles DO touch
-The value of each class is marked at the left side of each rectangle
Stem-and-Leaf Plot - CORRECT ANSWER -A graph to summarize continuous data by
dividing each data point into a stem part and a leaf part and listing these parts
-Is a histogram turned sideways with the data values listed instead of bars to show frequency
Skewed Right - CORRECT ANSWER -The tail of the chart is on the right side of the peak
Skewed Left - CORRECT ANSWER -The tail of the chart is on the left side of the peak
Bimodial - CORRECT ANSWER -Histogram has two peaks
Uniform - CORRECT ANSWER -Every bar on histogram is pretty much the same height
Summary Numbers - CORRECT ANSWER -A numerical quantity used to describe (or
summarize) data
