Descriptive Statistics
This measure of center is found by adding all values and dividing by the number of values.
What is the mean?
The difference between the largest and smallest value in a data set.
What is the range?
If 12 of 50 DVRs are defective, this is the probability a randomly selected DVR is defective.
What is 0.24?
These five values make up the five-number summary.
What are the minimum, Q1, median, Q3, and maximum?
The probability of an event occurring given that another event has already occurred.
What is conditional probability?
For the ages 40, 23, 32, 30, 33, 26, 25, 27, 25, 27, 32, this measure equals 27.
What is the median?
The square root of the sample variance.
What is the sample standard deviation?
If 3537 respondents use social networking sites and 1338 do not, this is the probability a random respondent uses social networking sites.
What is 0.726?
For the data set
\[ 5,\ 8,\ 10,\ 12,\ 15 \]
this is the median.
What is 10?
In a class of 30 students, 18 are female. If a student is selected at random and is known to be female, this is the probability the student is female.
What is 1?
For the ages 40, 23, 32, 30, 33, 26, 25, 27, 25, 27, 32, these values occur most frequently.
What are 25, 27, and 32?
A z-score greater than 2 indicates a value that is this.
What is significantly high?
The probability Mike correctly guesses Kelly's birthday on the first try, assuming 365 possible dates.
What is
\(\frac{1}{365}\)
?
For the data set
\[ 1,\ 2,\ 4,\ 6,\ 8,\ 10,\ 12,\ 14,\ 16 \]
the interquartile range is this value.
What is 10?
Out of 500 patients, 80 have a disease. Of those 80, 72 test positive. Given that a patient has the disease, this is the probability they test positive.
What is
\(\frac{72}{80}=0.90\)?
?
The statistic calculated as
\[ \frac{\text{minimum}+\text{maximum}}{2} \]
What is the midrange?
Using the range rule of thumb with
\[ \bar{x}=21.4,\quad s=4.6, \]
scores greater than this value are significantly high.
What is 30.6?
If the probability of an event is 0.03, this is the probability of its complement.
What is 0.97?
For the data set
\[ 2,\ 4,\ 6,\ 8,\ 10,\ 12,\ 14 \]
the first quartile is this value.
What is 4?
A survey found that 40 students play sports, 25 play an instrument, and 10 do both. Given that a randomly selected student plays sports, this is the probability the student also plays an instrument.
What is
\(\frac{10}{40}=0.25\)
?
For jersey numbers, the mean and standard deviation are not meaningful because jersey numbers are measured at this level.
What is the nominal level?
\[ z=\frac{x-\mu}{\sigma}, \]
Using this statistic measures how many standard deviations a value lies from the mean.
What is a z-score?
The probability that an event will occur plus the probability that it will not occur equals this number.
What is 1?
For the data set
\[ 2,\ 4,\ 6,\ 8,\ 10,\ 12,\ 14 \]
the third quartile is this value.
What is 12?
Among 200 people, 60 own a dog, 80 own a cat, and 30 own both. Given that a randomly selected person owns a cat, this is the probability they also own a dog.
What is
\(\frac{30}{80}=0.375\)?