Question

1. A track coach is trying to determine if a new training program will lead to better standing long jump results. She selects 20 of her athletes, tests their standing long jump distances, then has them take part in a 12-week training program. After they complete the program, she tests their standing long jump distances. (The distances below are recorded in meters.) Before 2.35 2.42 2.26 2.58 2.62 2.16 2.40 2.62 2.35 2.47 After 2.34 2.48 2.29 2.62 2.64 2.18 2.44 2.67 2.39 2.44 on WOHY 250 oho som man botantolino centros de base de todos os niet de 1 oboro doon (a) Construct a 90% confidence interval for the mean difference in jump distance (after-before). [5 pts] 20 how to w nocy 25000 tono midogo bandz to sidobo OD 909 longo way to sub adi vafo bands-oton Wormsdongo da sidan 200 nin mo of bowrolla ton o IMAXS HT MO (lotow bisa) VOSTOVA HTW HOW TO OG grow on tosial moldog ser ob of worlot s onoys most of to tridsvis 932 2 O bo son las son yamuoy getrol 2101025 10 ya bns zobuto 10 colocar lo anno solton yem tay na stoluowana tu 102 dolenone of by to monog worte o non sbobiniog niet dus word no gribnaqub well no vero 9100210 anno 9103 oy w s1002 m 2 wol toys (b) The creators of the program claim that their program significantly increases jump distance. Test this claim at the 5% significance level. od to nos od row Show on boto so slenog na tot blond vom uovani to yies no sniegobno i. Define the parameter(s) and state the hypotheses: [3pts] mich 12 10 bagno bas bobsod viral sorts or to breasts ir tuods inmonod na ng two moto mong stor nomizori borgarstwa toy libro os naruto sono costly on add no worlar ol 2012 at bogstong sun Bu folow 376 to 12 how mailul voli bababalworlamor now ob o non sols modu TOHY Tab ob es abone Oy ii. Find the observed sample statistic (using your calculator) and the test statistic (using a formula). Use proper notation for the sample statistic ( for p ), and clearly identify your test statistic as either a 2-score or a t-score. [4pt] da od szumi-sito nono le notion og at how im edilo noinog

Answer 1

first, We 4. A track coach recorded the difference in Jump distance. have to calculatē thee differen cuce (di) = (After Before). then, we have to find mean differeuce, and then standard deviation of difference SDd. I

difference (di) Before 2.35 2.42 2:24 After 2:34 2.48 - 0:01 0.06 0.03 2:58 2.29 2.62 2.64 0.04 0:02 2.62 2:16 8:18 0.02 2:40 0.04 2.44 2.67 0.05 2.62 2.35 2:39 2.47 2.44 oooh -0.03 0.26 ol I di So, Mean difference Cd) 2 to in 2 el 97.0 x 20.024 10-1 standard deviation, sod 1 {(di-d) 2-0-01-0-021)7 (0.06 – one 4+ (-0.03 -0.020) - 9 2 0.0.276

S CI 90%. * Since this is a paired data, we should use a paisud + statistic here. we have to constructa 909. Confidence Antenval bene. The-formula is given by the equation, at t* sod rn Where t* is the t critical value, al- 42 0.05 level of significance, and degrees of freedom = (n-)2 9 Now, tooos, q = 1:8331 So, the required CI is, Vio 20.026-0.016, 0·0267 0·016 10.01, 0.042) (6 The Creators of the program algo% 20.026 I 1.8331 0.0276 their program siguificantly 2 claim 2 that- Gnomeases Jump distances.

W so, our Ho! H 2 O Since, tobserved 2298. > to.08,9 21.8331 our parameter of interest is Mean difference Md 2. Ma-te Oull null and altunctive drypothes's arees 20 against Hi Md > 0 ( Sample mean difference, ło= 0.036 Sample standard deviation SDd 2 0·0276 We use a t-test statistic here. hd ta Sod vn Vio 28.98 We have to test the claim at 420.05 level of Siguificauce. since this is a elight tail test, a Only one tol 18331 So, we should suject our null hypothesi's. 2 0.026 0.0276 lies in on to005, 9 2