Stats

Which of the following is an example of RESPONSE BIAS?

Bob gives an answer to a survey question but his answer is incorrect.

Which of the following is the X variable in an experiment?

Independent variable, or factor

What does Q2 stand for?

all the above ( the 2nd quartile, the median, the 50th percentile)

Bob wants to estimate the percentage of people who own a dog in his town, and he goes to all the apartment buildings to carry out his survey. He leaves out all the houses in the town. What kind of bias is this?

bias due to undercoverage

The standard deviation has no units.

false

If a data set is skewed to the left, the mean is ____________________ the median.

less than

Mike marks down the gas mileage of his two cars every time he fills them up with gas for 6 months straight. At the end he notes that his Mustang gets better mileage than his Corvette. Is this an experiment or an observational study?

observational study

The slices on a pie chart represent relative frequencies.

true

The standard deviation can never be negative.

true

The starting point can affect the way a graph looks.

true

You can have two data sets with the same mean but different standard deviations.

true

What is the standard deviation of the data set 1, 1, 1, 1?

0

When a difference in treatment is decided to be due to more than random chance, what do you call the results?

Statistically significant

Which type of sample is used when you want to compare subgroups of the population?

Stratified Random Sample

A listing of all possible values in a data set and how often they occurred is called a data _____________________.

distribution

A flat histogram (with a line straight across) contains no variability whatsoever, according to our definition.

false

If there are a few very small values in a data set compared to the rest of the data, the mean will be larger than the median.

false

A _______________ is a way to graph quantitative data.

histogram

What kind of sample occurs when you put an ad in the newspaper and ask readers to take your survey?

self-selected sample

As we heard in lecture, the "average distance from the mean" is measured by the __________________________.

standard deviation

What is the most common observational study?

survey

An experiment imposes a _______________________ on the subjects, which makes it different from an observational study.

treatment

If you could choose four numbers from 1, 2, 3, 4 and repeated numbers were allowed (such as 1, 1, 3, 2), which set of four numbers would give you the largest standard deviation? (No calculations needed.)

1,1,4,4

Which of the following is an example of UNDERCOVERAGE?

Bob only surveys people in the dorms but he wants opinions of all OSU students

In the real estate example in the notes, which statistic was more attractive for the home buyers, the mean or the median?

median

If the mean of a data set is large, the standard deviation has to be large also.

false

The median must be one of the numbers in the data set.

false

If you add 10 to every value of a data set, what happens to the standard deviation?

it stays the same

A five number summary contains the min, max, Q1, Q3, and what other value?

all the above (the 50th percentile, the median, Q2)