MATH 1040 - EXAM 1

What is data?

Consist of info coming from observations, counts, measurements or responses

T/F: Nominal levels of measurement use math computations

FALSE - none

T/F: Interval data has an inherent zero

FALSE - ratio does

The graph to the right shows the responses to the question, "Does global warming contribute to El Nino?" Identify the level of measurement of the data listed on the horizontal and vertical axes in the figure. Horizontal: Response (very likely --> unsure) Vertical: Percent

Horizontal: ordinal Vertical: Ratio

What level of measurement can be ordered and differences between data entries are meaningful, but a zero entry is *not* an inherent zero?

Interval

What is the difference between class limits and class boundaries?

Class limits are the least and greatest numbers that can belong to the class. Class boundaries are the numbers that separate classes without forming gaps between them. For integer​ data, the corresponding class limits and class boundaries differ by 0.5.

What level of measurement is used for names, labels, qualities and has no math computations?

Nominal

Which level of measurement can have no mathematical computations?

Nominal

The list of books that your friend read for school for the past 5 months is shown below. Gone Girl Private London Spring Fever Threat Vector What is the data set's level of measurement? Explain your reasoning.

Nominal - data are categorized using names, labels, or qualities, but the data

The jersey numbers for players on a baseball team are listed below 10 7 40 13 9 12 15 What is the data set's level of measurement? Explain your reasoning.

Nominal. - data are categorized using numbers, but no mathematical computation can be made

What is the level of measurement for "happiness level (scale of 0 to 10)"?

Ordinal

Which level of measurement can be arranged in order, or ranked, but differences between data entries are not meaningful?

Ordinal

The regions with the 6 highest volumes of sales for a corporation last year are shown below. 1. west 2. ne 3. east 4. n 5. s 6. se What is the data set's level of measurment?

Ordinal - ranked or ordered in some manner (the sales can be ranked by the highest volumes but it is qualitative data)

What level of measurement is change in health (scale of -5 to 5) considered?

QUALITATIVE --> ordinal

Major, eye color and place of birth are all describing what type of data?

Qualitative

The regions with the 6 highest volumes of sales for a corporation last year are shown below. 1. west 2. ne 3. east 4. n 5. s 6. se Are the data qualitative or quantitative?

Qualitative

Determine whether the variable is qualitative or quantitative. Explain your reasoning. Colors of automobiles

Qualitative - attribute or labels

Determine whether the variable is qualitative or quantitative. Explain your reasoning. Gender of students in a class

Qualitative - attributes or labels

Determine whether the variable is qualitative or quantitative. Explain your reasoning. Amount of disk space in gigabytes

Quantitative - amount of disk space is found by measuring or counting

Determine whether the variable is qualitative or quantitative. Explain your reasoning. Weight

Quantitative - found by measuring or counting

Determine whether the variable is qualitative or quantitative. Explain your reasoning. Times to complete an obstacle course

Quantitative - numerical measurement

Determine whether the variable is qualitative or quantitative. Explain your reasoning. Times to run 100 meters

Quantitative - numerical measurements

The masses (in grams) of a sample of a species of a fish caught int he waters of a region are shown below: 22.7 23.8 23.9 23.4 20.3 19.3 Determine the level of measurement of the data set? Explain your reasoning.

Ratio - data can be ordered and differences between data entries are meaningful, and a zero entry is an inherent zero

Determine whether the variable is qualitative or quantitative. Explain your reasoning. Favorite color

The variable is qualitative - color describes an attribute or characteristic

What is the difference between a random sample and a simple random​ sample?

With a random​ sample, each individual has the same chance of being selected. With a simple random​ sample, all samples of the same size have the same chance of being selected.

What is qualitative data?

consists of attributes, labels, or non-numerical entries (categorical)

What type of statistics consists of tables, charts, averages etc?

descriptive

What are the branches of statistics?

descriptive and inferential

What is the level of measurment for "marital status"?

nominal

What level of measurement are allergies listed on a medical form considered?

nominal

What levels of measurement can be qualitative?

nominal ordinal

What are the different levels of measurement?

nominal, ordinal, interval, ratio

What is a parameter?

numerical description of a population

What is a statistic?

numerical description of a sample

What is quantitative data?

numerical measurements or count

What level of measurement can rank or order the data in some manner, without having meaningful differences between the data entries?

ordinal

Which level of measurement can be qualitative or quantitative?

ordinal

What are some benefits of representing data sets using frequency​ distributions?

organizing the data into a frequency distribution can make patterns within the data more evident

What is the numerical description of a population?

parameter

What level of measurement is height considered?

quantitative --> ratio

What is the level of measurement for "height"?

ratio

Which level of measurement has a true (inherent) zero?

ratio

What is the ratio level of measurement?

ratio of 2 data values can be formed zero entry is an inherent zero (implies "none") e.g. height (can say someone is twice as tall as somebody else)

What is the numerical description of a sample?

statistic

What is a population?

the collection of *all* outcomes, responses, measurements or counts that are of interest

What are the experimental units

the individuals on which the experiment is done

What is statistics?

the science of collecting, organizing, analyzing, and interpreting data in order to make decisions

What are inferential statistics

using sample data to draw conclusions about a population

What type of zero does interval level of measurement have?

zero represents a position on a scale (not an inherent zero; place holder) e.g. year of birth --> the year 0 exists

Is this an example of descriptive or inferential statisics? Population: all male students (parameter) - average height Sample: 50 random selected students (statistic) - average ht from sample

Descriptive

T/F: Interval data can be ordered

TRUE

A Pharmaceutical company wants to test the effectiveness of a new allergy drug. The company identifies 250 females​ 30-35 years old who suffer from severe allergies. The subjects are randomly assigned into two groups. One group is given the new allergy drug and the other is given a placebo that looks exactly like the new allergy drug. After six​ months, the​ subjects' symptoms are studied and compared. Identify a potential problem with the experiment design being used and suggest a way to improve it.

There may be a bias on the part of the researcher if the researcher knows which patients were given the real drug.

What is a sample?

a subset, or part of, the population e.g. population: all responses of US employees; sample: 834 surveyed "responses"

What is an inherent zero?

a zero that implies none -ratio

`A pharmaceutical company wants to test the effectiveness of a new allergy drug. The company identifies 250 females​ 30-35 years old who suffer from severe allergies. The subjects are randomly assigned into two groups. One group is given the new allergy drug and the other is given a placebo that looks exactly like the new allergy drug. After six​ months, the​ subjects' symptoms are studied and compared. What is the: experimental unit? treatment?

experimental unit: 30-35 years old who suffer from severe allergies treatment: new allergy drug

Select 3 examples of data sets that do not have inherent zeros below. Temperature in degrees F Average IQ score of a high school class Average monthly precipitation in inches Average age of college students in years Maximum wind speed during a hurricane A student's level of happiness measured from 0 to 10

i.e. the zero represents a position on a scale, place holder -Temperature in degrees F -Average IQ score of a high school class -A student's level of happiness measured from 0 to 10

What type of statistic draws a conclusion?

inferential

Select 3 examples of data sets that have inherent zeros below: Temperature in degrees F Average IQ score of a high school class Average monthly precipitation in inches Average age of college students in years Maximum wind speed during a hurricane A student's level of happiness measured from 0 to 10

inherent = 0 implies none -Average monthly precipitation in inches -Maximum wind speed during a hurricane -Average age of college students in years

What is the level of measurement for "year of birth?"

interval

What level of measurement is year of birth considered?

interval

What levels of measurement can be quantitative?

interval ratio sometimes ordinal

What is the difference between ordinal and interval data?

interval has data that has differences in the data entries that is meaningful e.g. year of birth

What are descriptive statistics?

involves organizing, summarizing and displaying data e.g. tables, charts, averages