In this section ol the test, you will hear talks and coDversations. .. 22 - Pefiect TOEFL Junior Proctice Tesl Book 'l tvnovellas.info refer to the follo$,ing. No part of the TOEFL® Junior™ Standard Practice Test book may be The ideas expressed in the reading materials contained in the practice test do not. Level: Elementary to Upper-intermediate Perfect TOEFL Junior Practice Test Book 2 is the first book in a three-book series. The goal of this book is to provide.
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How to Get Ready to Take the TOEFL Junior Standard Test. Sample Questions Answer Sheet. .. The TOEFL Junior test is available throughout the world. The TOEFL Junior Standard Free Practice Test Helps Your Students Prepare TOEFL Junior test at your institution, please complete the application form (PDF). See sample questions for the TOEFL Junior Standard and Comprehensive tests. Supplement for Test Takers with Disabilities or Health-Related Needs (PDF).
Each TOEFL Junior score report includes a Lexile measure, which puts the ability of the reader and the difficulty of the text on the same scale. This takes the guesswork out of choosing books at a student's reading level. Browse the ever-growing Lexile Book Database and find the right books for your students. You can choose when you want to test, the size of the group and various situations in which to use the test, including placement, monitoring progress and more. This makes the tests an essential tool for: Placement in intensive English-language programs requiring academic English proficiency at a college or graduate level.
C ft mares frequently. C Their leader, Santa Anne. D Thcy never should hav. According to the teacher, which planet A Thc solar l,stcm has the most moons? Why does the teacher talk about the outer planets? What can be inferred about Saturn? B To locu5 on their compositions C lt has a corc that is rocky. Wlar is another name for Lbe inner planets?
Mark lan ten the letter ofthe correct aDswer on yotr answer sheet. Here are two sample questions: D strike The correct answer to Sample I is C , "are caused. This Fdday night at seven otlock, the drama club is pleased presenting the production B for presenting this production I. The play c is directed will direct by Edward Holliman, the schoolt art teacher. The play will be lLl set some ot the me astoe some rime aside!? This spring semester, rhe school is going ro C suspend classes for two week5.
A number of area businesses I A in several differem felds B with several differences in frelds 6. C have agreed to take on student jnterns. By doing from these internships, students will be able to get hands-on expe ence at jobs I actor ls irectil'lg C that they may do in the future.
Studenls mav also leel free to arrange their own D how they are doing otlect internships. Contact Mr. Farguson or Mr. Whirtaker lor more informarion. We hope lr a big success B 8. A In addition ro the schedule B Consequently, the schedule 9. B in up to five departments.
Among them are the cancer ward' the D ior all live departments. For rhe past couple of yean, I have considered becoming a docror in the future. Acrually seeing sone docrors a! I might decide that being a doctor is not the D frnalization profession for me. Or I mighr see all of the doctors at work and feel that I simply musr what will happen? B when it happens? Dear Helga! A exchange B exchanges -i. I would like to welcome you to our school. I know rhat being an C exchanged D exchanging student can be difncult, especially when you are so far away from your home.
I A improving. B happening. As you may have heard, the Thanksgiving holiday is C approaching. My entire family D insist lntil A getting us ro hang out.
B hanging out with us. D get to hang our wirh us. I hope you can come as I am lesson D feast A have B are having Let me know ilyou are inrercsted. These days, there are many students who do not attend physical schools but why it is homeschooling. B what is a homeschool. While these studenc D where they are homeschooled. I A primarily B solely C relatively D cautiously One reason for this concerns athletics. In many American states, homeschooled students are permitted to play on their local schools' athletic teams.
This is good news for the schools A exception B exceptions The students who attend D exceptionally actual schools are mostly accepting ofthe homeschooleis. They usually have no problems A upset B curious C worried D hostile So they tend to bombard the homeschoolers wirh numerous quesrions.
Some ofthem 8l will have benefitted A for individuals of their age. B of rhe individuals who have aged. D by individuals that age. The Hubble is superior to Earth-based telescopes A both the size and quality B either the size or the quality The first concerns c neither has size nor quality D not only sizes but also qualities A what is sc B they have to scan the skies,.
D production of blunv images. B as sooo as possible. By doing that, D sooner than is possible. A unique B known i5, The originr oi the majoritl of. Its origins are both well known and c certified. A Basketball, a sport B Basketball, the sport J-. James Naismith in December A to be cold and snowy, verse itself. B coldness and snoq J8, Since winters in that region of Massachusetts tended C cold and snow, D being cold and snowy, Naismith wanted to crcate a sport that men could play indoon in a gymnasium.
He came A rules basically lor ten games.
B the basic rules for ten games. D ten basic rules for the game. B that are still utilized roday. Several olthese rules arc ones ' where people dre u lng rne. D rvhat were utilized today. C humbled origins came the game of basketball. Before you start, read the sample tert and the sample cluestions belorv. Sample Text r popular Sample Question 1 What is this text mosdy about?
Please read the following carefully as it descdbes my expectations of you during this class. Xveryone must do the reading assignments since we will have class discusstons. Your participalion in these discussions will be a part ten percent of your grade in my class. In addition, we will have one written homework assignment each week. In most cases, it will be a short 3-page pape!
We will have four tests during the semester. Each one will be worth twenty percent of your final grade. There will I will call on you during class. Please attempt to answer be times when my inquides. Do not simply confess that you do not know the corect rcsponse.
I expect everybody to try hard in my class. I want you all to take notes during my class. I will provide you with an outiine of the rnaterial we will study each day; however, you need to write down the impoitant information that I mention in your notebooks.
I welcome questions in class and urge you to ask them if you ever fail to understand somethins. ID line ro, tbe word conless is closesr in n most meanlng to graded A blarne will be l.
Based on the note, what is probably B admit true about the students' homework C decide assignments? Which of the following is NOT men- D The students have to show the teacher- tioned in the note about something that thet notebooks at times. A schedule for the school'. As these are the inilial mectings, studeDts Nho desire lo ioin these clubs must be prcsentj othen.
In addition, the chrss club and thc hikrng clr. AJ rhe requireci number of stlrdcnts D Thev have lo rell rhejr classmates B borh clubs about the chan! C the fhll and spring scmestefs l nore students Whar can be inlerred from rhe scheduls 1 about the photography dub?
A It will t-. The students, professor, and three graduate assistants headed to a valley nea. Cheaha Mountain. The valley was not previously known Io have any lossils in it. However', Lwo months ago, some campers in the valley stumbigd upon some bones sticking out from the ground. When they brought them to the museum, lhey were told that Ihe bones were those of a brontosaurus, a species of dldosaur.
Thanks to a gener. They spent most of both Saturday and I Sunday carefully digging in the area. We,re not suae t which anjmal they're from, but the proiessor assured us theywere from a dinosaur.
The students, all of whom inrend to major in science at college, are looking 1i forward to retuming this coming weekend. There,s enough money in the granr I for the next month, so we should get to return at least thr. A A stu. Did They Live around Hcfc? D A representatjle of the Damke Foundauon ,. In line 6, the phrase stumbled upon is:. According to the article, when will the I ill I students go back to the dig site? In line 7. Why does the author mention the Damke Foundation?
A To claim it has an intercsi in dinosaurs B To notc a group thrt i9 financing the students C To focus on its relationshlp wirh ihe Donoho School D To claim that it sponsor many local orgs '! People halc long wondered if rhc planet is home to allcrn life. Over th. What is the best title for the passage? D Many people began to think about t0, Which of the following can be inferred N'lafs. C HLlmans hope to visit ii someday.
Martian face? B It proved there was life on Mars. C It u,as found ncar some cllannels. D ]t is Localed rear some nresirs. In line the phrase akin to is closest 15, in meaning to A uscful to Wiat did, Mats Global Surveyor do? Worlds, D prcciscl! Lnd TV I nrean, no one butl,ou got higher than a 92 on thc scF ence test X'lrs. Sellers just gave us back. Eren rorse, Jeremv had told him that hc had not studied for Lhe tr n. Spill the beans, and fili me in," demandcd Don. I pav attention in class, and I take good notes.
That's reall al1 there is to it. I had forgotten abour that," said Don. I1's realh simple. According to the passage, all of the story?
Wly is Don in a bad mood? Vy'hat doesJeremy tell Don to do? B Go ovcr his notes ar hone everl night rn. B He is willing to rutor L on in son]e of A He will develop bener study habirs his classes, dlan Jeremy.
C lle intends 1o follow Jer-em! Il The Creat Lakes ale Lhc l. Ontafr r. Hurolt, l]1d Super. Lales O tar. J l-rie, Huron. Ar tlle tjrne oliberi aleeLldr. The gre. Lhe nlcltinq icc rurne.
Lake Supcfior is the dccpcst: All fnc of the lakes are connccrcd bv boLh r.
Tolonto, Deuoit. Ihis hes trnnsfortncd qt: In line r7, the word immense is closest in A The lonnarior ofrhe Crea! Which of the Gieat Lakes is the biggestz s.
Lake I iA Lrke Huroll 4t. Why does the author talk about the St. Creat I B The movement of glaciers in thcm. Which of r be folJowing is true regarding the islands in the Great Lakes? B Some are morc rhan: D N'lost of rhem are errremelt large. I lr a iiri! Follow along as you listen to the directions to the. Each talk or con- versation is followeal by one question. Choose the best answer to each question'and mark the letter ofthe correct answer on vour answer sheet.
You will hear each talk or conversation onlv one time, Here is an exampler jp What does the girl mean? B She is nor going to be a mcnbcf oirhe baDd- iC she thinks rhar the band b no Jorger fun. The conect ansu'er is B , "She is not going to be a member ofthe band. Why is the boy talking about the school will download? A To insruct thc stLrdents on how to do l. What are tle speakers mainly discussing? How does the principal punish rhe boy? A By giving lim dcrenrioD 8. C Ii can result in decreasjng , WIy does the teacher mention that it is unemplovment.
D it affects the middle class ihe mosr. C To advise dre studenr not to fall behind A Ask tlre students a quesiion D To praise the student for her worll B aor'ri.
What are the speakers maidy discussing? A fhe girl's faiLure to conuibute 1 r Lhe A All oi his extrircurricular acti! C His pan-iiftc joh Sctting D All of his club nl. B She is rlisappoinred. C she is irnpressed. A lle is a stnr athlci.. B FIe works hardcr than most students. A She car gea neNous in class at rime. Why does the te. D She tlinks she understands the material A To enJourage the boy ro applv ro , do next?
What is the teacher going to do in their r l, r. According to the teacher, what did the A The bo -. A He wrote about the rvlong book. C Shc rhinks that the boy is rrying ro D He wrote a paper rhar wa5 tod shoft. D The boy needs to apologize to Ms. Hooper, A Rewrile hjs paper 20, Wtrat traffic violation does the boy say B Do some research that he committed?
D Study granmar B He ran a red light. C He ignorcd a srop sign. D FIe did not tum his headliglrrs on. What is the main topic of the discussion? A llenewable rcsources B How to sevc energy According to the boy, why did Ms. Hooper drive back to school? D How ro plcseNe the environment A The wearher was too bad lor rhe boy to drive in.
A Walk or rjde bikes more often anylror--e. B Stop using fossil fue1s entircly D She disliked how thc bo! A He lacks experjence driving a car B He is going ro graduare rhis ycar.
C He is close fiiends lvith the girl. H,'up r. Wlat does the teacher imply about the LS paper rs lc'f to heat homes? Atacama Desert? B To show how it would aciually halm B Mofi peoplc consider it to be a semi- gher grade thc envlfonntent arid desen.
A How diamonds afc created r too sholt. B Why dialnonds arc so valuabLe Its Thcy are both clean and cheap. C How people search fbr diamonds Lfter school iC More research needs to be done on D what makes the region rich in them. According to the woman, what two forces i0.
What is the main topic of the talk? According to the teacher, what kind of J , Why does the woman talk about rnment desert is the Gobi Desert? A A hot dcseft A Ic Jc.. Why does the matr suggest that he can Wilkes Booth? A The woman reccnily dug up a dianond. D To focus on the major everts in his Jlre A She was thc m;rn s teacher in rhe past. B She f-ound lhe largest diamond in rhe 41, What does the teacher imply about area.
President Lincoln? Cl Sh. Lee and Ulysses S. Granr 42, What will the teacher probably do next? In this section of the test, you will anslver ,12 questions found in seven difterent lbout texts. Within each text are boxes that contain four possible ways to complete a sen- tence. Choose the word or u'ords in each box that correctlv comDlete each sentence.
While some forest fires C are caused h1 humrns. In fact, some places:. Dear Stacy, Thanks for telling me about the computer club. I had nor been planning ro join any clubs this year as I was going to locus solely on my studies. Howevet, once I heard A were planned by the computer club, B planning the computer club, 1.
I have you to thank for that. It looks like we're going to do A entertain. B enterraining. D entertainment. A more fun than J, T jusr hope rhar ir's C the most flm the math club was last year.
That club D as fun as possible A cancellation. B thrill. D challenge. It is impoitant to remember that the organisms that live in an ecosystem vary depcnorng rn any eard A obstacle. B appearance. For instance, organisms thar B mrgnre c detest in hor and dry climates are I D submit A as likely B one of the most likely c more likely to dwell in deserts than rhey are in rainforests.
The local D the most likely cluD A the local wildlife will affect. B affects the local wildlife. D has been alfected by the locai wildlife. Foi example, rhere afe animals that have adapted to life in mountains and high aititudes, so it is clear that they will not be found in grasslands, swamps, or other similar ecosysrems- rtr;,riet. A hold B will hotd 9, Please remember that elections for student government are going to C be held D holding A interest B interested Only students who have a GPA of 3.
Likewise, any students who have been suspended in A requested B delayed ll. Each student Fohibited D encouraged A what decides rc run B who decides ro run t2. Dear parcnts, hold: Ocrober L end B ends lsrdentr -J. The bake. We would like D enchng I y igible to in A gather B contribute: D collect udenr You can feel fiee rc download items such as cookies and cakes from bakedes, or you can bake sales and donations.
B of the donations at the bake sale. We appreciate all c the bake sale's donations. D donations to the bake sa1e.
Attendees will be able to download delicious baked goods: As always, the C ofthe bake sale is to raise objective D reminder more than the money B the most of the money This yeal the school's athletic much money as possible as D more money than A desperate B divisive If you have any questionsj what we desired raising D it is our desire to raise contact Faith Rawlings at We hope ro see all of you at the bake sale. A which can be fantasy. B one of which is fantasy. D some of which are fantasies.
B ingredients. C constituents. H The characters may cast magic spells, or their world may be magical. Fantasy literature also I contains a variety ol fantastic creatures such as dragons, unicorns and centaurs, A what possesses magic powers.
B which magic powers are possessed. C what they posses in magic powers. Middle Eanh, the world ofJ. B one such made-up place. These worlds may be D making up a place. Invtet,com ,vww.
Elves dwarves, orcs, and goblins are among the existence of other mces. B the other races that may exist. D the races that have existed.
A hero. C competition D warfare A defeat B defeating l These refer to the following letter, among To All Srudentr: A informed B announced 19, Mr. Richards has just C the school that he will only be teaching with us insisted D alarmed A Moving back, he is B After moving back, he will i0, for rhe -err rwo week. C He has moved back ro Texas to D He is moving back take care of his parents, both of whom are elderly.
Please give your best wishes to Mt Richards before he leaves. Richards has been with us for five years, and it is safe to say A morc popular than him. B as popular as that. As you all know, Mr.
Richards D more than he is popular. Since we are in the middle of the semester, we do not A swift B thorough We will do rhal reduced D ve fied during the winter break. Forunately, Mrs. Richardt classes.
She is an outstanding teacher, and you will all surely benefit ftom being in her clast Dee Gorey Principal 96 Pe: The students were given one hour to compose their works. Thirty-two students entered the competitionj and their works A rated B guaranteed J7. B that consisted with three judges. Two were teachers from Central High School c who consists with three judges. D consisted of three judges. The Judges D repealed unanimouslv declared Alicia Walker!
C entitlement i t Fdther: Walker's essay will be A returned B entered 41, C submilred. FL ,lLrnicr i'.. Before ou start, read the sample text and the sample questions below Sample Text r second Sample Question 1 What is this text mostly about? C Ii can. Llcscfis o'rL'ffight. Thp corrpct dn"ucr: So that nteans.
Fortunatel], you don,t have to r. You cari pur- chase all sorts of electronic equipment, including calculators, desktop computersfand notebook computers. And here's the bcst part: From now until the beginning of the school year, re are having a back to-school sale.
And be sure to visit our boys' and g. Yoo simply can,t bcat Carter,s Dcpartment Storc tor quality and price. Which of the following statements is true adveItisement? L t0 saart n t nave L In Iine z, the phrase stocking up on is 5. What is the discount on a Dotebook a trip to. Al utilizing 1A 25q. To all students enrolled in any science laboratory class: There have been a couple of alterations in all of our science laboratory classes since the beginning of the semester.
The lab fees must be paid in full no later than Friday, September In addition, all students must download the requislte safety gear for their classes. In the past two weeks, four pairs of safety glasses and h,vo lab coats have gone miss- ing. The school simply cannot afford to continue replacing this equipment, so now all students must have their own items, which they will be expected to hold on to. While it may not seem fair to punish everyone for the actions of a few this is the only option we seem to nave.
What is the note mainly about? In line 10, the word r-equisite is closest iD 10, 'lhe peifonnance of some students in meaning to iheir classes iA safest Sorne changes corlcerning tl,c achool'9 Bt minimu.
In line , the word which refen to rc1led in ay , A the school 00 since Which class requires the payment of a B this equipmcnt Tease in fee? While Which of the following statements does B lt needs to be updated. C it is of fairly high qualir. A Lab supplies cost morc. I n a nlrivte t. Dear Parents, Il's that time of the year Lo slart thinking about our annual spdng festival. As you know, the school holds the festival for a couple of reasons- The ffrst is to engender a sense of comDlrnity between the school and the resldents of the neighborhood.
The second is to help raise money lor the school to use in a variety of manners. They will primarily be held in the school gym and auditodum as well as on the foolball field. Thil year, we have a large number of special activities planned. Please consult the attached sheet to see the events ihat have been scheduled. Since we have so many activilies planned, rve are counting on you, our students' parents, to assist us.
Ifyou can spare even one or two hours of your time, rve would appreciate it. Please contact Mrs. What is the purpose of the letter? In Line 9, the word consult is closest in A To let the parents knorv hon, their meaning to children arc pcdbrning A edri B To dcscribc an e','ent to be helcl in the B chech fall C rcgard C To praise the pafcnts fof rheir devoiion D print to the school p!
I 'ing the ri. Coral reefs are rocklike protrusions thar el tcnd fiom a coastline jnto the ocean. Tbey arc made from coral. Coral polyps appear to be small planls lo manv peoplc. Thev grou, rn clustels and sccrete a substance nlade of calcillm carbonatc that protects thetr. TlT rs sub-stilnce. Thev ate r. There are a cou- ple ol reasons that manv sea clcaruies, particularl-v fish. The tlrsr: The hard, rockv lcefs can rvound large fish, sLrch as sharks.
Due to the ab- sence of manv voracious predators, smallef llsh often 1av rheir eggs in coral reefs.
When the flsh hatch, the reefs act as sa. Coral requires jdeal condirions to 1ive. Yet the ocean is not static but is in a constarrr state of change. Sometimes the watef temperature in a place r. This can 1esuft iD the destiuction of an entire reef. As for manmade problcms, there are tr. First, pollution caused b," hunans such as the dumping of chemicals in the sJater can ki11 coral.
Some ofthem cslhe! Onra smaller sdale, somc people cut olT coral from reeli to make jewelfy from or to use lor home aquariums. All ol these faclors combine to endanger manv ofthe world's coral reefs. What does the author imply about coral 2J. In line tJ, tbe word sanctuaries i5 closesr pob? D containcrs rcy grow: Which of the following statements does According to the passage, which is neces- paragraph t support?
D orJl.. CO rn. There have been many famous detectives in literature. But one of the first - and certainly the most famous is Sherlock Holmes. Sherlock Holmes made hjs fifst appearance in the work,4 Study in Scdrlet, which was published in lBBZ Holmes instantly became a popular literary figure with the general populace, who demanded that Doyle write more sto es involving hjm.
Doyle complied and eventually wound up writing fifty-six short stories and four novels that featured Holmes. Together with his partner, Dr. Watson, Holmes uses his powers of observation to detect clues that can help him solve the cases 1i he accepts.
Holmes has an incredibly sharp mind that enables him to determine who the guilty party is or whdt the problem is. Holmes also is a master ofdisguise, which he proves many times, and he is skilled at boxing as well as sword fightjng.
While Holmes often solves cases lhat are unrelated to one another, he has a nemesis with! That person is Professor Moriarty, the leader of a crime ring in London. In one of the stories, The Final Problem,Holmes and Moriarty fight one another and fall to their deaths by plunging down a steep cliffnear a waterfall.
When he wrote that story, Doyle had tired of Holmes and wanted to kill offthe character. I l In line 24, the phrase rcfiained from ir? A stopped LA He considefed bccoming a detecrjve in B resumed and four his vourh. C posttoned creating iB He uas a bcstselling aurhor dllring his D continuecl '. Among lile. Why does the autior mention Tle lisguise, stories he is involved in. Hound of the Baskemilles? In C lt is the titlc of one of his well knorvn rer and A It was too dilllcuh for him to come u]l 0r mofe u'irh net, storylines.
D I-le eDcouraged Dr. Watson ro become mofc obsen'ant. Solar eclipses are easil,v lhe more specracular. For a solar. This is a solar eclipse. A solar eclipse may be either total of partial. The sky darkens, and it appears to be nighftime. A solar eclipse onl,r.
During one, the moon appears vefy orange and is practically red in color. There are tll''o different t-vpes of lunar ecllpses. Taken together, ihe result is that lunar ecllpses happqn more fre4lentl], lhan so iar eclipses. In addition, lunar eclipses may iast for hours and can be seen from a wider area on the pianet. Junior p. J llook I '". T ftei. Il Two! In line 6, the word spectacular is dosest in meaning to A distinct Which of the following is true regarding rlipse Io lunar eclipses?
Lll impressir,e e sun is A Thel occur more olien than solar C lost lasting nakes lt eclipses. D common s. In line 8, the word it refers to on. The A the moon's orbit C They reslrlt in the moon disappearing ftom sighr. I rses ale mo0n B rhe sun C the moon D Thet last for a shorter tirne thar solar ccllpscs. I D Eanh. Lno tne C Superstitious peopie believe they bring D blocked 'm00n, bad Iuck. Why is the moon able to cover the sun extrenel-v bdght.
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Oat tO 3. Llr r sen. L nrr't. L lnrr l ll r,iie. I hir's nro Lrtrd. I iLr. Howdin you do on rlre poprest we had in IIr. Ii's 9i3-L: What do yo! Preiiv lvell. I answered nine out olrhe tcn quc-i tions correcrly. Howd you do on it? He'- onc ofmy panners on rhar group projecl Gl I made a coupl. I r,,t,. Arc gramnarand spellingthar lmtoranr? Yox nccd ro do is arriving soon. The boy starts the conversatiiD by stating. I rrjed o finish all ofrhc marh problenrs, brtr I early lE00s- His armie!
Hc was llnallY ainjngall defened ar rhe B: Mrth troblems? Oh ml, Soodness. I rorallr'-. Since Dr. Walt"Canpbell is "an expert on French B: YN havc llme to do hisiorr"'and he is soing to speak about Napoleo. Gl You re righr. The girl states that she had forgottento do it. Br Ms. So she is w: Why do l,ou need an exrension?
Erery orhcr srudent jn rhe chss is going ro rurn his or he The teacher suggests to the bol, "Why don,t you so: Br wcll. Did yo! I sure did. Congrarularions on winnjng.
Yeah, Angie did agfeatjob, didnl she? Whai do rou rncan? She's an ourstnnd ing goalk. Lr Iou re suppos. Bur ro. Booo l. The soL- cer leam is oflesler importance.
Gl Uh, t guess I played all righr. And you had sonrc grear tsur your dxsses are nrore inporranr. So l,m go r8.
Ob, rhanks. Yes, ma am. Bur I doDt Lnow holv good it. Thar's one way ofpuftjry ir. Do you have a gane w: Do yolr besr. Use rhis tinre wisely. The jng all ofrhe infornralion you need first is on luesdaynighr.
All rishr. Br I'lldo mybes! I can definitety ar- 10 icnd the Tuesday game, bur I,m nor su. At the beginnitls ofthe conversatioD, ihe boyrels theieacher, 'I needto iatk about the report that G: We corld use some big crowds. Yeah dral makcs sense. Theydiscuss the tas. I don r have rhal Lon t lou lhe sirl tells the boy, "Hos'ever se have tso sames -qc nucli athleric ability. Ja nighr. Yeah, neithef do I. So, uh, can lou rell m. I acrualh kbd or cnjoy scien.
Then, she says, "No! Thar sounds grefi. I'll see tou arthe lab ih. We could use somebig crowds.
We playmuch: Atthebeginning ofthe conversatior, the girl aslsthe boy what the teacher was speaking with him about. Ascience fair? Thark peculjar. About Mr. The solid curve in each frame is the estimated mean score on the first test administration as a function of interval, while the dashed curve is the estimated mean score on the second test administration as a function of interval. Figure 3 Open in figure viewer PowerPoint Smoothed trends of initial score solid line and second administration score dashed line as a function of interval, separately for each skill area and the total.
As shown in Figure 3 , the distance between the dashed and solid curves, representing average score gains, tends to increase as the interval increases. Generally, the effect is modestly evident from the low end of the interval distribution to the middle and very evident at the higher end of the interval distribution, consistent with Table 2 , in which the interval was treated as a categorical variable.
The two curves start to diverge at an interval of about days, and this pattern is consistent for all subtests. This explained why the average interval was much longer for this group. Although these students may constitute a distinct population, they do not differ much from students in other countries with respect to overall initial score. Hierarchical Linear Models The descriptive information is consistent with the hypothesis that the test is sensitive to changes in English ability as a function of interval.
The main motivation for conducting HLM analyses was to quantify the relationship between interval and gains in a way that would not be distorted by potential differences in student populations across countries and to obtain a valid test of statistical significance of this relationship. Our HLM is designed to achieve both of these goals. We first present what we call the base model and then present what we call the alternative model, which we use to address a particular potential source of bias in the base model.
The effect of interest is the coefficient on interval. All other effects in the model are included only to improve the estimate of the effect of interval and to get an appropriate measure of uncertainty about this effect. We now describe these other effects and why they should achieve these goals. We include dummy variables in the model for individual countries to prevent country differences from biasing our estimated relationship between interval and gains.
As noted previously, there were large differences in the distributions of interval across countries, especially at the higher end of the interval distribution. These differences could have led to bias in the estimated relationship between interval and score gains if students from different countries had systematically different average values of interval because of unobserved test taker characteristics that were related to score gains. It seemed reasonable to assume that such characteristics might exist, so we needed to treat differences among countries as a potential confounding factor and find a way to prevent this potential confounding factor from biasing the estimated coefficient on interval.
Treating countries as dummy variables avoids this potential confounding, as it ensures that the effect of interval is estimated using only variation in interval among students but within countries i.
Differences in the average value of interval across countries do not therefore contribute to the estimated effect of interval, and therefore, differences among students in different countries cannot be a source of bias.
We include random effects in the model for testing groups. By definition, students in the same testing group had the same interval; thus, it was not possible to include dummy variables for testing groups because that would have left no variation with which to estimate the effect of interval.
However, it was possible to include random effects for testing groups. Doing so is beneficial and important. As described earlier, students belonging to the same testing group were likely to share similar instructional or testing experiences. These factors could have caused students who shared a testing group to have systematically higher or lower gains than would have been predicted based on only the interval and the country for that group.
The testing group random effects are introduced to account for unobserved differences in the average gains in different testing groups that remain after accounting for both interval and country effects. Accounting for this variation through the random effects leads to a more accurate estimate of the effect of interval and an accurate standard error for this estimated effect. Our model assumes a linear relationship between interval and gains within countries.
It is reasonable to question whether a nonlinear relationship would be more appropriate. The linear specification is also supported by a graphical analysis. Figure 4 provides a scatterplot of total gains versus interval where both quantities are centered by their respective country means. This represents the relationship between total gains and interval within countries, aligning closely to how Model 1 identifies the effect of interval through the use of country dummy variables.
The fact that these two curves nearly coincide supports the assumption that the relationship between gains and interval within country is well approximated by the linear specification of Model 1.
Figure 4 Open in figure viewer PowerPoint Scatterplot of total score gain versus interval where both are centered around their respective country means.