Homework One Math 227 PDF

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Ambe rRod r i gue z Ma t h227( s e c t i on22 411)-St a t i s t i c s We s tLosAng e l e sFa l l2 020

Homework One 1. Thef o l l o wi n gda t ar e pr e s e n tt hea g e s ,r oun de dt ot h ene a r e s ty e a r ,ofar a ndom s a mpl eofs e v e n c ur r e ntUSs e na t or s :7 2,77,66,60,75 , 59, 83 a . Wha ti st hepopul a t i oni nt hi spr obl e m? - USSe na t or s b . Wha ti st hes ampl e ? - 7c ur r e ntUSSe na t or s c . Wha ti st hev a r i abl e ? - The i ra g e s( r ounde dt ot hene a r e s ty e a r ) d. I st hev a r i a bl equant i t at i v eorqua l i t a t i ve ?I fqua nt i t a t i v e ,i si tdi s c r e t eorc ont i nuo us ? - Theva r i a b l ei sdi s c r e t eq ua nt i t a t i v e 2. Li s t , de s c r i be ,a ndpr o v i deonee xa mp l ef ore a c hofFourLe v e l sofMe as ur e me nt . - Nomi na l( e x. De moc r a t ,gr e e n, Re publ i c a n, Li b e r t a r i a n,I nde p e nde nt ) - Or di na l( e x . Gr a de sA, B, C, D. F) - I n t e r v a l( e x.1$t o2 $i st hes a mei nt e r v a la s50$i st o51$ - Ra t i o( e x.Da y0, Da y1,Da y2) 3. Wal ma r tSt or e s :Cu r r e nt l y ,t he r ea r e4227Wa l ma r ts t o r e si nt heUni t e dSt a t e sa n d a n ot he r 3210s t o r e sout s i d eo ft heUni t e dSt a t e s . a . Ar et henumbe rofWa l Ma r ts t or e s( di s c r e t eorc ont i nuous ) ? - Di s c r e t ebe c a us ei ti sc ount a bl e b . Wha ti st h el e v e lofme a s ur e me ntf ort h enumbe rofWa l ma r ts t or e si nd i ffe r e nty e a r s ? ( no mi nal , or di nal , i nt e r v al , orr at i o ) - Or d i na l c .I ft hes ur v e yi sc ondu c t e db yr a ndo ms e l e c t i n g1 0c u s t ome r si ne v e r yWa l ma r ts t or e , wha t t yp eo fs a mp l i n gi sus e d ?( r andom,s ys t e mat i c , c onv e ni e nc e ,s t r at i fie d,c l us t e r ) d. I ft hes ur v e yi sc ond uc t e db yr a ndo ms e l e c t i n g20Wa l ma r ts t or e sa ndi n t e r vi e wi n ga l lt he e mp l o y e e sa tt hes t or e s ,wha tt ypeofs a mp l i n gi sus e d?( r a ndom,s y s t e ma t i c ,s t r a t i fie d, c l us t e r ) 4. De t e r mi newhe t he rde s c r i pt i veori nf e r e nt i a ls t a t i s t i c swe r eus e d a . Thea v e r a g epr i c eofa3 0s e c onda df orAc a de mi ca wa r d ss ho wi nar e c e nty e a rwa s1. 90 bi l l i ondol l a r s . b .I n2025,t hewor l dpopul a t i oni spr e di c t e dt obe8bi l l i o npe opl e . c .I nawe i ghtl os ss t udyus i n gt e e na g e r sa tBos t onUn i v e r s i t y ,52% oft hegr oups a i dt ha t t he yl os twe i ghta ndke pti toffb yc ount i n gc a l or i e s .

d. TheDe pa r t me nto fEc o nomi ca ndSoc i a lAffa i r sp r e di c t st ha tt h ep opul a t i o nofMe xi c o Ci t y ,Me xi c o,i n2030wi l lb e23 8, 647 , 000pe opl e . e . For t yf o urpe r c e ntoft hepe opl ei nt heUni t e dSt a t e sha v et ypeObl oo d . 5. St a t ewhi c hs ampl i ngme t hodwa sus e d . a . Outof10hos pi t a l si namuni c i pa l i t y ,ar e s e a r c he rs e l e c t sonea ndc ol l e c t sr e c or d sf o ra 24hourpe r i odont het ypeofe me r g e nc i e st h a twe r et r e a t e dt he r e .( r andom,s y s t e ma t i c , c onv e ni e nc e , s t r a t i fie d,c l us t e r ) b .Ar e s e a r c he rdi vi d e sagr oupofs t ud e n t sa c c or di n gt oge nde r ,ma j orfie l d ,a ndl o w, a v e r a g e ,a n dhi ghgr a depoi nta v e r a g e .The nr a ndo ml ys e l e c t ss i xs t ud e nt sf r o me a c h gr oupt oa ns we rqu e s t i o nsi nas ur v e y .( r andom,s y s t e mat i c ,c onv e ni e nc e ,s t r at i fie d, c l us t e r ) c . Thes ub s c r i b e r st oama g a z i nea r enu mbe r e d.The nas a mpl eoft he s epe op l ei ss e l e c t e d us i n gr a ndom numbe r s .( r andom,s ys t e mat i c , c onv e ni e nc e , s t r a t i fie d,c l us t e r ) d. Ev e r y1 0t hbot t l eofe ne r gi z e ds odai ss e l e c t e d,a ndt hea moun tofl i qui di nt hebot t l ei s me a s ur e d .Thepu r po s ei st os e ei ft hema c h i ne st ha tfil lt hebo t t l e sa r ewor k i ngpr ope r l y . ( r andom, s y s t e mat i c ,c onv e ni e nc e , s t r a t i fie d,c l us t e r ) e . Ar e s e a r c he rs e l e c t se v e r y571t hs o c i a ls e c ur i t ynumbe ra nds ur v e y st hec or r e s pondi n g pe r s o n.( r andom,s ys t e mat i c , c onv e ni e nc e , s t r at i fie d,c l us t e r ) f . Tode t e r mi nec us t ome ropi ni onoft he i rs a f e t yf e a t ur e s ,Da i ml e r -Chr y s l e rr a ndoml y s e l e c t s140s e r vi c ec e nt e r sd ur i n gac e r t a i nwe e ka nds ur v e y sa l lc u s t ome r svi s i t i ngt he s e r vi c ec e nt e r s .( r andom, s y s t e mat i c , c onv e ni e nc e , s t r a t i fie d,c l us t e r ) g . Al a r g eCompa n ywa nt st oa dmi ni s t e ras a t i s f a c t i ons ur v e yt oi t sc ur r e ntc us t o me r s .Us i n g t he i rda t a ba s e ,t hec ompa nyr a ndo ml ys e l e c t s40c us t ome r sa nda s kst he ma boutt he i r l e v e lofs a t i s f a c t i o nwi t ht hec ompa n y .( r andom,s y s t e mat i c ,c on v e ni e nc e ,s t r at i fie d, c l us t e r ) h. Tod e t e r mi neh e rbl oo dpr e s s ur e ,Br i t ne yd i vi de suphe rd a yi nt ot hr e ep a r t s :mor ni n g , a f t e r no on,a nde v e ni n g .Shet he nme a s ur e she rbl oo dpr e s s ur ea t4r a ndom s e l e c t e dt i me s dur i n ge a c hp a r toft heda y .( r andom,s ys t e mat i c , c onv e ni e nc e , s t r at i fie d,c l us t e r ) 6. Thef o l l o wi n gb a rgr a phr e pr e s e nt st hea mou ntofdi ffe r e ntbe e r ss ol di nSe ymou r ’ sSa l oond ur i ng t hemo nt hofOc t obe r .

a . Whi c hbr a nds ol dt hemos ti nOc t ob e r ? b . Wha ta r et hec l a s s e s ? c . Wha ta r et hec l a s sf r e que nc i e s ? d. Wha ti st hedi ffe r e nc ei nt henumbe rofb e e r ss o l dbe t we e nMi l l e ra ndCor on a ? e . Wha ta r et hec l a s sr e l a t i v ef r e que n c i e s ? f . Wha ta r et hec l a s spe r c e nt a g e s ? g . Tr a n s l a t et heba rgr a phi nt oapi ec ha r t . 7. Ho us i ngAr r ange me nt s :A que s t i on na i r eo nh ous i n ga r r a n g e me nt ss ho we dt hi si n f o r ma t i on obt a i ne df r om25r e s ponde nt s .( H=hous e , A=a p a r t me nt , M=mobi l ehome ,C=c ondomi ni um. ) H

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Da t aa r es or t e da ndr ounde dt ot hene a r e s tun i tf ors i mpl i c i t y . Us e5numbe rofc l a s s e sCons t r u c t : a . Fr e que n c ydi s t r i but i on b .r e l a t i v ef r e qu e nc ydi s t r i but i o n. c . Cumu l a t i v ef r e que nc ydi s t r i but i on. d. Dr a wf r e que nc yd i s t r i b ut i onHi s t ogr a m e . Dr a wOgi v e f . Dr a wf r e que nc yp ol y g on. 10.Fort h es a mpl eda t a :7, 5,1,9, 5,3, 4,3,2, a nd6,c ompu t e r a .s a mpl eme a n b . me di a n c . Mode d. Mi d r a ng e e . St a nda r dde vi a t i on f . Va r i a nc e g . Ra ng e 11.Tr ue /Fal s e ? a .I fe a c hof25s a mpl ev a l ue si se qu a lt o20mi n, t hes t a nda r dd e vi a t i onoft hes a mpl ei s0. b . Fora n ys e tofs a mpl ev a l ue s , t hes t a nda r dde vi a t i onc a nn e v e rbeane g a t i v ev a l ue . c .I ft hes t a nda r dde vi a t i onofas a mpl ei s3k g ,t he nt hev a r i a nc ei s9kg . 2 d. I ft hev a r i a nc eofas a mpl ei s16s e c, t he nt hes t a nda r dd e vi a t i oni s4s e c . e .I ft hes t a nda r dde vi a t i onofas a mpl ei s25 c m,t he nt hev a r i a nc ei s5c m2. 12. Er r or sonat ypi ngt e s t :Thef r e qu e nc yd i s t r i but i o noft henumbe rofe r r or st ha t10s a mpl e s t ude nt sma deonat ypi n gt e s ti ss ho wn.

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15.I nas e tofda t a ,bl oodp l a t e l e tc ount sofwome nh a v eabe l l s ha pe dd i s t r i but i onwi t hame a nof 280a nds t a n da r dd e vi a t i onof65. Wha ti st h ea ppr o xi ma t epe r c e nt a g eofwome nwi t hpl a t e l e tc ount s ?

a . be t we e n150a nd410? b . be t we e n215a nd345? c . be t we e n215a nd410? 16. Th r e es t ude nt st a k ee qui v a l e nts t r e s st e s t s .Wh i c hi st hehi g he s tr e l a t i v es c or e ? a . As c or eo f143onat e s twi t hame a nof127a ndas t a nda r dde vi a t i onof32. b . As c or eo f92o nat e s twi t hame a nof88a ndas t a nda r dde vi a t i o nof16 . c . As c or eo f19o nat e s twi t hame a nof16a ndas t a nda r dde vi a t i o nof4. 17. I fy ours c or eont hi shome wor ka s s i g nme nti sc o n v e r t e dt oaz s c or e ,whi c hofz s c or ewo ul dy ou pr e f e r ? 2. 00, 1. 00, 0. 00,1. 00 , 2 . 00Wh y ?...