Elementary Statistics Unit 1

Main two types of data

Descriptive statistics

Branch of statistics concerned with collecting and organizing data

Inferential Statistics

Branch of statistics concerned with drawing conclusions from data

Quantitave Data

data that can be measured

Qualitative Data

Categorical or attribute data

Continuous Data

Data that can be obtained by measuring. Can have any value.

What type of numbers are used for Discrete Data?

What type of numbers are used for Continous Data?

The population of a small town is 2000 people. 380 people in the town have o-positive blood. It is published that 38% of the town has o-positive blood. What kind of statistic is this?

A pollster wants to estimate the proportion of voters in a certain town who are Democrats. He goes to a large shopping mall and approaches people to ask whether they are Democrats. Is this a simple random sample? Explain.

A _________ is a number that describes a sample

A _________ is a number that describes a populaiton.

Nominal or Ordinal: The names of streets in a town

Nominal or Ordinal: The movie rating G, PG, PG-13, R and NC-17

Nominal or Ordinal: The winners of the gold, silver, and bronze medals in the Olympics

Discrete or Continous: The number of female members of the U.S. House of Representatives

Discrete or Continous: The amount of water used by a household during a given month

Discrete or Continous: The number of stories in an apartment building

Discrete or Continous: A person's body temperature

Interval or Ratio: The year you started school

Interval or Ratio: Your age in years

Interval or Ratio: The time that your first class starts

Interval or Ratio: The price of a loaf of bread

The characteristics of individuals about which we collect information are called

The values of variables are called

Variables that classify individuals into categories are called

________ variables are always numerical.

Qualitative variables can be divided into two types: ________ and _______

A ____________ variable is a quantitative variable whose possible values can be listed.

________ variables can take on any value in some interval.

Qualitative variables describe how much or how many of something there is.

A nominal variable is a qualitative variable with no natural ordering.

A discrete variable is one whose possible values can be listed.

A person's height is an example of a continuous variable.

Nominal or ordinal: Tge categories Strongly disagree, disagree, neutral, agree, and strongly agree on a survey

Nominal or ordinal: The shirt sizes of Small, Medium, Large, and X-Large

Nominal or ordinal: This semester, I am taking statistics, biology, history, and English

Nominal or ordinal: In the track meet, I competed in the high jump and the pole vault

Discrete or Continuous: The amount of caffeine in a cup of coffee

Discrete or Continuous: The number of steps in a stairway

Discrete or Continuous: The amount of charge left in a phone battery

Discrete or Continuous: The number of electrical outlets in a coffee shop

Interval or Ratio: The year of your birth

Interval or Ratio: The weight in pounds of a sack of potatoes

Interval or Ratio: The water temperature, in C, in a swimming pool

Interval or Ratio: A student's GPA

A utility company sends surveys to 200 of its customers in such a way that 100 surveys are sent to customers who pay their bills on time, 50 surveys are sent to customers whose bills are less than 30 days late, and 50 surveys are sent to customers whose bills are more than 30 days late. Which type of sample does this represent?

A sample of convenience is ______ when it is reasonable to believe that there is no systematic difference between the sample and
the population.

The manager of a restaurant walks around and asks selected customers about the service they have received. Which type of sample does this represent?

In a study, 200 patients with skin cancer are randomly divided into two groups. One group receives an experimental drug and the other group receives a placebo. Is this a randomized experiment or an observational study?

Qualitative or quantitative? Is the number of points scored in a football game qualitative or quantitative?

Nominal or ordinal? Is the color of a phone nominal or ordinal?

Discrete or continuous? Is the area of a college campus discrete or continuous?

What kind of sample is this? . Website ratings: A popular website is interested in conducting a survey of 400 visitors to the site in such a way that 200 of them will be under age 30, 150 will be aged 30-55, and 50 will be over 55.

What kind of sample is this? Favorite performer: Viewers of a television show are asked to vote for their favorite performer by sending a text message to the show.

What kind of sample is this? School days: A researcher selects 4 of 12 high schools in a certain region and surveys all of the administrative staff members in each school about a potential change in the ordering of supplies. Which type of sample does this represent?

Political polling: A pollster obtains a list of registered voters and uses a computer random number generator to choose 100 of them to ask which candidate they prefer in an upcoming election.