MAT 152Name: _____________________________

LAB Chapter 1_2

ROUNDING: If rounding is required, round to 2 decimals.

1. Classify the underlined portion as either a parameter or statistic.Circle the correct choice.

a)In a calculus class of 28 students, 25% are female.parameter statistic

b)In a survey of 1,052 adults, 62% said the economy was the number one issue for the upcoming election.parameter statistic

c)Suppose a sample of 375 CVCC students is obtained, and from this sample we find that 67% have a smartphone.parameter/ statistic

2. Fill in the correct term; circle your answer: A statistic describes a______________, whereas a parameter describes a __________________.

3. Classify each of the following variables.Circle the correct choice for each part.

a)number of pets you own

Is this variable qualitative or quantitative?qualitativequantitative

If applicable, is this variable discrete or continuous?discretecontinuousnot applicable

b)area code

Is this variable qualitative or quantitative?qualitativequantitative

If applicable, is this variable discrete or continuous?discretecontinuousnot applicable

c) birth weight of a newborn

Is this variable qualitative or quantitative?qualitativequantitative

If applicable, is this variable discrete or continuous?discretecontinuousnot applicable

d)favorite pizza delivery company

Is this variable qualitative or quantitative?qualitativequantitative

If applicable, is this variable discrete or continuous?discretecontinuousnot applicable

4. Determine the level of measurement of each variable.

a)The musical instrument played by a music student.

Nominal

Ratio

Ordinal

Interval

b)The medal received (gold, silver, bronze) by an Olympic gymnast.

Nominal

Ratio

Ordinal

Interval

c)The height of a tree.

Nominal

Ratio

Ordinal

Interval

5.Decide whether each scenario describes an observational study or an experiment.If the scenario is a study, then decide whether it is a cross sectional study, case control study, or cohort study.

a)A researcher sets up a booth at the mall and hands out surveys to selected people to assess spending habits, including how much people spend on average during a trip to the mall.Questions include:"Did you make any purchases today?", "How many stores did you visit?", "How much money did you spend today?"

b)A researcher sets up a booth at the mall outside the food court and asks people to try two different hamburgers, both are new burger options for a restaurant, and pick his or her favorite.The researcher is trying to assess the best new burger option to introduce at a restaurant.

6.Decide what type of sampling method is illustrated.Circle the correct choice.

a) The Student Government Association (SGA) wants to know the satisfaction level of students with the current cafeteria menu.Members of SGA set up a table inside the student union and ask every fifth student to fill out a survey, starting with the second student who enters the student center.

simple random stratifiedsystematiccluster convenience

b)A travel industry researcher interviews all of the passengers on five randomly selected cruises.

simple random stratifiedsystematiccluster convenience

c)24 Hour Fitness wants to administer a satisfaction survey to its current members.Using its membership roster, which is listed in alphabetical order, the club uses a random number generator to select 50 members from the list.Those members are surveyed about their level of satisfaction with the club.

simple random stratifiedsystematiccluster convenience

d) You want to get information on who is the most popular candidate in the upcoming election.You choose your 10 closest friends to answer a survey about election preferences.

simple random stratifiedsystematiccluster convenience

e)The names of 20 employees are written on 20 cards.The cards are placed in a bag, and three names are picked from the bag.

simple random stratifiedsystematiccluster convenience

7.Suppose you want to understand how the American public feels about certain political issues.You decide to create a survey and collect your answers via telephone calls.What are some potential sources of bias?Give 2 specific examples, and identify the type of bias using correct vocabulary.

8. Use the following scenario: A professor wanted to determine if the sorting speed (requires manual dexterity) of people is different between their dominant hand and non-dominant hand.The professor recruits 25 students.Each student is asked to sort a pile of mixed dried beans (kidney beans, pinto beans, and black bean) into separate piles.The time it takes is measured.Each student performed the sorting with the dominant hand and non-dominant hand; which hand was used first was alternated among the 25 students.

a) What is the response variable?

b) What is the explanatory variable?

c) What are the experimental units?

d) What type of experimental design is this: completely randomized or matched pairs?

9. Use the following scenario:A researcher wants to test the effects of a new type of fertilizer on grass growth.She has fifteen recently mowed adjacent plots of land.She randomly chooses five and labels them "A".The next five randomly selected plots are labeled "B" and the remaining plots are labeled "C".She gives all of the "A" plots no fertilizer, all of the "B" plots the old fertilizer, and all of the "C" plots the new fertilizer she developed.After 30 days she measures the grass height.

a) What is the response variable?

i.the 30 days

ii.grass height

iii.the 15 plots of land

iv.which type of fertilizer was used

b) What is the explanatory variable?

i.the 30 days

ii.grass height

iii.the 15 plots of land

iv.which type of fertilizer was used

c) What are some of the other factors or lurking variables?List three.

d) What type of experimental design is this: completely randomized or matched pairs?

10.500 students at Valley High School were asked "What foreign language are you taking this year?"The responses are shown in the table below.

Language Frequency Relative Frequency

French 125

Spanish 285

German 55

Not enrolled in foreign language

Create a Relative Frequency Distribution for this data by filling in the column above.

11.Decide whether the graph below is a good graph or a misleading graph for the information.Briefly explain your decision.If the graph is misleading, then redraw it so that it is not misleading.

A survey was distributed to 100 people asking "What is your favorite ice cream flavor?"The options were vanilla, chocolate, or other (includes things like strawberry, rocky road, etc).The results are displayed in the following graph.

12. Mary gives out a survey asking people to choose their favorite desert from a list of options.From the results, she creates a relative frequency distribution.However, water is spilled on the table and one entry is unreadable.Her table is shown below.

Desert Relative Frequency

Chocolate Chip Cookies 0.3

Apple pie 0.07

Pound cake 0.02

Ice Cream

Other 0.3

a) Help Mary by filling in the missing entry.

b) What is the most popular desert?

c) If 200 people were surveyed in order to come up with the above table, how people answered that apple pie was their favorite dessert?

13.The following data gives the percentage of unemployed people in selected cities in the US.

9.6 12.3 10.4 11.0

7.8 11.5 10.2 8.5

9.2 7.6 10.9 9.6

11.6 10.5 9.2 12.5

Create a frequency distribution (table) for this data, using a first lower class limit of 7 and a class width of 1.

14.Based on your frequency distribution from #12, create a frequency histogram.

15.Suppose we create a histogram for the variable "annual household incomes in the US."Would you expect the histogram to be uniform, bell-shaped, left skewed, or right skewed?Explain briefly.