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Unformatted text preview: AP Statistics
Chapter 1/Chapter 2 PracticeTest a Name Date Period 'or questions 15, determine if the statements are True or Folse. Write the word True or False on the line next to the problem. 1.
2.
3. 4.
5. A numerical data set is called continuous if the set of possible values forms an interval. A data set is called a categorical data set if the” individual observations are quantitative responses. Eg Stratified random sampling is a sampling method that allows more accurate inferences to be made about a population. 8+ Simple random sampling is a sampling method which is objective and free from investigator bias.
Convenience surveys are a good method by which to acquire information from subjects in a study. m For each multiple choice question, carefully consider each possible answer and select the best choice by circling the letter of the answer. 6. Al Al Bl Cl Under which of the following conditions is it preferable to use stratified random sampling rather than simple
random sampling? ' The population can be divided into a large number of strata so that each stratum contains only a few individuals
The population can be divided into a small number of strata so that each stratum contains a large number of
individuals The population can be divided into strata so that the individuals in each stratum are as much alike as possible
The population can be divided into strata so that the individuals in each stratum are as different as possible The population can be divided into strata of equal sizes so that each individual in the population still has the same chance of being selected. George and Michelle each claimed to have the better recipe for chocolate chip cookies. They decided to
conduct a study to determine whose cookies were really better. They each baked a batch of cookies using their own recipe. George asked a random sample of his friends to taste his cookies and to complete a questionnaire
on their quality. Michelle asked a random sample of her friends to complete the same questionnaire for her
cookies. They then compared the results. Which of the following statements about this study is fa_lsg?
Because George and Michelle have a different population of friends, their sampling procedure makes it difficult to compare the recipes.
Because George and Michelle each only used their own respective recipes, their cooking ability is confounded with the recipe quality
Because George and Michelle each used only the ovens in their houses, the recipe quality is confounded with the characteristics of the oven Because George and Michelle used the same questionnaire, their results will generalize to the combined ' I population of their friends
E) Because George and Michelle each baked one batch, there is no replication of the cookie recipes. 8. Which of the following can be used to show a causeand—effect relationship between two variables? A) A census . A controlled experiment C) An observational study D) A sample survey E) A cross—sectional survey 9. To check the effect of cold temperature on the elasticity of two brands of rubber bands, one box of Brand A and
one Box of brand B rubber bands are tested. Ten bands from the Brand A box are placed in a freezer for two
hours and ten bands from the Brand B box are kept at room temperature. The amount of stretch before
breakage is measured on each rubber band, and the mean for the cold bands is compared to the mean for the others. Is this a good experimental design? A) No, because the means are not proper statistics C) No, because more temperatures should be used
for comparimn No, because temperature is confounded with B} No, because more than two brands should be brand
used E) Yes iii]. A high school statistics class wants to conduct a survey to determine what percentage of students in the school
would be willing to pay a fee for participating in afterschool activities. Twenty students are randomly selected
from each of the freshman, sophomore, junior and senior classes to complete the survey. This plan is an example of which type of sampling? A) Cluster ® Stratified Random
El) Convenience E) Systematic C) Simple Random
11. Which of the following is NOT a characteristic of stratified random sampling? A} Random sampling is part of the sampling procedure
El) The population is divided into groups of units that are similar on some characteristic
C) The strata are based on facts known before the sample is selected
D) Each individual unit in the population belongs to one and only one of the strata.
@ Every possible subset of the population, of the desired sample size, has an equal chance of'being selected. 12. A group of students has 60 housefiies in a large container and needs to assign 20 to each of three groups labeled
A, B and C for an experiment. They can capture the flies one at a time when the flies enter a side chamber in the
container that is baited with food. Which of the following methods will be most likely to result in comparable groups of 20 houseflies each? A) Label the first 20 flies caught as group A, the second 20 caught as group B and the third 20 caught as group C. B) Write the letters A,B and C on separate slips of paper. Randomly pick one of the slips of paper and assign the
first 20 flies to that group. Pick another slip and assign the next 20 flies caught to that grup. Assign the
remaining flies to the remaining group. C) When each fly is caught, roll a die. If the die shows an even number, the fly is labeled A. if the die shows an odd
number, the fly is labeled B. When 20 flies have been labeled A and 20 have been labeled B, the remaining flies
are then labeled C. @ Place each fly in its own numbered container (numbered from 1 to 60) in the order that it was caught. Write the
numbers from 1 to 60 on slips of paper, put the slips in a jar, and mix them well. Pick 20 numbers out of the jar.
Assign the flies in the containers with those numbers to group A. Pick 20 more numbers and assign the flies in
the containers with those numbers to group B. Assign the remaining 20 files to group C. E) When each fly is caught, roll a die. Ifthe die shows 1 or 2, the fly is labeled A. if the die shows a 3 or 4, the fly is
labeled B. If the die shows a 5 or 6, the fly is labeled C. Repeat this process for all 60 files. 13. A study showed that persons who ate two carrots a clay had significantly better eyesight than those who ate less
than one carrot a week. Which of the following statementis) is (are) correct? 5 'I) This study provides evidence that eating carrots contributes to better eyesight
II) The general health consciousness of people who eat carrots could be a confounding variable
lll) This is an observational study, not an experiment A) I only C) land ll only a) lllonly llandlllonl\{l;ll ndlll For each of the free response questions, please address the prompt thoroughly, but directly. Write in complete sentences.
14. An experiment is conducted on the internet usage of teenagers in Washington State. Can the results of this experiment be generalized to all teens in the US? Why/Why Not? N9 W0 W: Snmylﬁ m3 Wham teem in washinﬁltrt, “01' W
with? U9. 15. A consumer group conducts a reliabilitytests on electrical appliances. To determine the reliability of 1996
Maytag washing machines, 25 Maytag washing machines are tested and their reliability assessed. Describe the population and the sample for this problem. W Péyvla’rien is all my Ma le Wéhirij Mixtures Wt Smyhii M as rekcbglj My;er 16. The fly fishing club, consisting of 200 members, wishes to estimate the amohjt‘of time a typical member spends
fishing each year. There is not enough time to‘survey all 7200*members, so it is decided that a simple random
sample of 25 members will be selected from the club membership roster. Describe how this might be‘done. Pvt 'l'he names a? all 290 WWW in)» a hat Mist walla
draw will 25 natures. This will he Yak Sample. . Milled rep imment. . ‘
17. We need to survey a random sample ofthe 300 passengers on a flight from San Frantisco to Tokyo. Name each _ sampling method'described below: A) Pick every 10m passenger as people board the plane Sﬂghmth B) From the boarding list, randomly choose 5 people HE; first class and 25 of the other passengers Smgiiéird ra Din Snmglinj C) Randomly generate 30 seat numbers and survey the passengers who 5 the Sim is random €ahx?“@ D) Randomly select a seat posi ion (right window, right center, right aisle, etc.) and survey all the passengers sitting
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18. Explain the concept of a doubleblind study and why it is important / COM “ﬂew \h Ul AUU‘WLC VOW we, $U$J£6% a M (16%.
Know Witch, W “game/kt. “is WM h Welda has“ 19. A runningshoe manufacturer wants to test the effect of its new sprinting shoe on lOO—meter dash times. The
company Sponsors 5 athletes who are running the 100meter dash in the 2004 Olympic Games. To test the
shoe, it has all 5 runners run the IUDmeter dash with a competitor's shoe and then again with their new shoe. The company uses the difference in times as the response variable. a) Suggest some improvements to the experiment design. . at MW?” Sam’ng [/ayf‘r 7;:qu 5) J7; pgan .77 m M “4w
FWD (’77 fie/f” fvj’MIwJ/zc h: M swam Cbﬁllﬂmii») Wm M Mini? mama mw‘aéézr a away/ﬁr Ma... in) Why might the shoe manufacturer not be able to generalize the results they find to all runners? 771‘? 4% will} ffoW/ ﬂying/c aﬂbiﬁzj; Whig}, Cam/[5L
hat/F CaH—Q'n’rmbli drFﬁml/pcer % n W ,Wﬂmi. 20. Some people claim they can get relief from migraine headache pain by drinking a large glass of ice water.
Researchers plan to enlist several people who suffer from migraines in a test. When a participant experiences a
migraine headache, he or she will take a pill that may be a standard pain reliever or a placebo. Half of each group will also drink ice water. Participant will then report the level of pain relief they experience. A) Sketch a diagram of this experimental design. _ an <1“, Wlwé . “9 Hz. 9 Memsgvﬂ
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B) According to the criteria for good experimental design, does this appear to be a good experiment?
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21. Some schools teach reading using phonics (the sounds made by letters) and others using whole language (word
recognition). Suppose a school district wants to know which method works better. Design an experiment for the school district to use. Be sure to address all of the components of a good experimental design. /My{ré mMaryufy {zgp’h V; 734; faraway for ﬁnch“, mhwﬁvﬁ 5]“
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This note was uploaded on 04/01/2012 for the course STAT 1000 taught by Professor Xu during the Spring '12 term at Manitoba.
 Spring '12
 XU

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