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Data

The information we gather with experiments and with surveys is collectively called

Design

Planning how to obtain data to answer the questions of interest refers to

Description

Summarizing the data that that are obtained refers to

Inference

Making decisions and predictions based on the data refers to

Inference

Predicting the preference of all of the coffee shop customers based not the taste test results refers to

Design

Randomizing the order in which the samples of each brand were given to each customer refers to

Description

Stating that 90% of the taste testers preferred the new brand is an example of

All American adults

In 2006, the General Social Survey asked "would you like to see more or less government spending on natural disasters?" Of the 1496 respondents, 723 responded "more" or "much more." The population consists of

The 1496 respondents

In 2006, the General Social Survey asked "would you like to see more or less government spending on natural disasters?" Of the 1496 respondents, 723 responded "more" or "much more." The sample consists of

False

Parameter values are usually known

A parameter

A numerical summary of the population is called

Statistic

A summary measure that is computed from a sample to describe a characteristic of interest is called

Parameter

The average GPA of Harvard's 2007 graduating class.

Statistic

The proportion of teenagers in a nationwide survey who stated that they consumed alcohol on a regular basis.

Parameter

The proportion of regional flights for United Airlines that were considered on-time during the month of December, 2007.

True

Random sampling enables the sample to be a good reflection of the population.

True

A lobbyist for a major airspace firm assigns a number to each legislator and then uses a computer to randomly generate ten numbers. The lobbyist contacts the legislators corresponding to these numbers. This technique produces a random sample.

False

A lobbyist for a major airspace firm wants to get the opinion of state legislators on an issue of importance to his industry. The lobbyist contacts 10 state legislators at the Top of the Mark Restaurant during a lunch break and each one is polled about the issue. This technique products a random sample.

Applet

A short application program for performing a specific task is called an

Quantitative

The amount of time spent watching television or playing video games is considered a significant factor on predicting childhood obesity. 290 parents of school-aged children were asked to estimate the number of hours per week that their child spend watching television or playing video games. This is an example of what type of variable?

Categorical

Your statistics teacher has gathered information on each of the students in your class in order to illustrate the difference between categorical and quantitative variables. For each student, she has recorded their major, gender, age and height. The variable "major" is an example of what type of variable.

Continuous

The time it takes an athlete to run 100 meters.

Discrete

The number of calls received between 8 a.m. and 5 p.m. by a technical support professional.

False

If a distribution is very highly skewed, the mean is usually preferred over the median because it better represents what is typical.

False

In skewed distributions, we expect the values of the mean, median, and mode to be approximately equal, since they are all measures of center.

Description

The following statement refers to which aspect of a statistical study: "The average age of the students in a statistics class is 25 years?"

Statistic

The average weekly amount spent on groceries by a family of four based on a random sample of 100 families.

False

To estimate the percentage of defective items a machine is producing, a quality control analyst inspects the first 100 items produced in a day. This technique products a random sample.

Property of R

R does not depend on which variable is treated as the response variable, r is always between -1 and 1, the closer r is to zero, the weaker the linear relationship between x and y, and r only measures the strength of the linear relationship between x and y.

Population growth

A study shows that the amount of chocolate consumed in Canada and the number of automobile accidents is positively related. Which of the following identifies a potential lurking variable?