STA Test 1
A fitness instructor measured the heart rates of the participants in a yoga class at the conclusion of the class. The data is summarized in the histogram below. There were fifteen people who participated in the class between the ages of 25 and 45. What percent of the participants had a heart rate between 130 and 150 bpm?
47%
1 standard deviation from the mean x̅ - s x̅ + s
68% of the data x̅ - s x̅ + s
Which branch of statistics deals with the organization and summarization of collected information?
Descriptive
Quantitative data is always _____ (_____ or _____)
Numerical (continuous or discrete)
A box plot allows us to see which 3 characteristics for a data set:
Skew, spread, and symmetry
Lengths of pregnancies of humans are normally distributed with a mean of 265 days and a standard deviation of 10 days. Use the Empirical Rule to determine the percentage of women whose pregnancies are between 255 and 275 days.
68%
2 standard deviations from the mean x̅ - 2s x̅ + 2s
95% of data x̅ - 2s x̅ + 2s
3 standard deviations from the mean x̅ - 3s x̅ + 3s
99.7% of data x̅ - 3s x̅ + 3s
A distribution curve that is right-skewed has:
A longer tail on the right side
Which of the following correctly describes the relationship between a parameter and a statistic?
A statistic is calculated from sample data and is generally used to estimate a parameter.
A high school student took two college entrance exams and scored 1120 on the SAT and 27 on the ACT. Suppose that SAT scores have a mean of 950 and a standard deviation of 140 while the ACT scores have a mean of 22 and a standard deviation of 4. Assuming the performance on both tests follows a normal distribution, determine which test the student did better on.
ACT
A study was done to determine the average commute time per week to and from class for an SPC student attending a lecture class. For convenience, a sample of 60 students was taken by randomly selecting a lecture class on the Gibbs campus (30 students), and also a lecture class on the Clearwater campus (30 students). The students selected for the sample were then asked where they were commuting from, when, and how often. The information was then entered into a GPS system in order to obtain estimated commuting times.
All SPC students who attends lecture class
At a local community college, five statistics classes are randomly selected out of 20 and all of the students from each class are interviewed.
cluster
A community college student interviews everyone in their statistics class to determine the percentage of students that own a car.
convenience
A study where a drug was given to 23 patients and a placebo to another group of 23 patients to determine if the drug has an effect on a patient's illness.
experiment
The median LSAT score reported by a Law School is 170. Which of the following is not correct?
half of the students have an LSAT score of 170
From past figures, it is predicted that 19% of the registered voters in California will vote in the June primary.
inferetial
five number summary of positions
minimun, Q1, median, Q3, maximum
Qualitative data can be considered ______ or _______
non-numerical or categorical
A study where a political pollster wishes to determine if his candidate is leading in the polls for an upcoming election.
observational study
eye color
qualitative
The cost of a Statistics textbook.
quantiative
Measures of position are _________, ___________, _____________ _____, and __________ ____.
quartiles, percentiles, interquartile range, and percentile rank.
Measures of dispersion are _____, ________, and ________ _________.
range, variance, standard deviation
If we know the standard deviation but want the variance, we would have to _____ the standard deviation.
square
50 sophomores, 30 juniors and 20 seniors are randomly selected from 500 sophomores, 300 juniors and 200 seniors at a certain high school.
stratified
Every fifth person boarding a plane is searched thoroughly.
systematic
skewed left
tail goes to the left (mean<median)
skewed right
tail goes to the right (mean>median)