looking for professional in statistics?

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l. Belo*,is a histogram for rents pairl rn Logan. Find tire heighi of the niissing block frcm 350 to 400. Estimate the percenlage of rents less than $400 pcr t't-totlti'i. ilstimale

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percentage of rents less than $425 per moffih, ;\pproximately, what is tl:e average rcnt'/

Estimate the mediar rcnl.

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One queslir:n on the 2000 ccnsus ftrrrn asks how far you hal'e 1o comnrute to work.

\\.,hen the data is analyzed, it is for-urd that the average distance is 13.3 miics, rviih an Si-) rrl16.8 miles. \V|ich of the follorving skctches do you think best app.roxirlalt:s the histograt:: lbl the

ilistenee trave.led'l lJo -rou think the median distartcc travclecl r',ot:ld'ce surallei than 13.--l

milos. hrgcr tiren 13.3 niles. or abor"Lt 13.3 miles?

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3. A table for the scores on a statistics n{dterm is givcn bclolr:. '1-he ctrass interrals inclr"tde the leli endpoil:t, but not the right. Drarv the histogram.

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Points Number of Students rruicltl. kw i4 !rI 0-s0 25

50{0 100 70.80

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B0-90 25 q0-r 00 25

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4. The heights (inchesi for tlie sta(ir:g ftve on a **olxen's basketball leam afe 66 ' 6',7 ' 69' 71 '

atd72. a) Find their avaage height'

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b) Find the SD of the list.

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-\ - .1-X-{ (xg ,is-:6q ut - 3?' 4 67 *$ r\ €- *lL -* l* bq'64 ? 61 ro ?l-d4 r: )trtt a 1 * *L:*-r#ffad

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5. The average of a list of numbers is 1943 and the SD is b8' nun:ber on the list, tlnri the averagc and SD of the neq' list'

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If -vou add 2012 to each

6. The ar.erage r-rf a list of 12 numbers is 9 anri the SD is equal 1o 3 !f il.ic runbers 4 and l2 are incluilerl with rhis list ol numbors, wi:at is the average anii Sil oi lhc nei.'' l:-r')tl)L;

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Examples of Correlation

1. 'lToulci the correiation i:etween the age of a used car and its price be positive or negalive?

\\&y are childreri shoe sizes positively correlated with reading ability?

\Yhy is daily chocolate consumption positively correlated *'ith daily autt: accidents?

4. Far e reprsentative sarnple of ears, wcald the c*relation between the age of the car a&d its g*soline $con$ruy (miles per gailon) be positive or aegative?

The correlation betrveer: gasoline econorry anC income of owner fturs our to be positive. Horv do you account fbr this positive association?

ls the cor:elation between the heights of husbands and wives in the U.S. around -0,9 , -0"3 , f:' , or 0,9 ?

7. lf u'ornen alr.val's married. men rn'ho were exactly 4 inches talier, what u,culd the con'elation between their heights be?

8. Three data sets are coliected, aad the correlation coefficient is computed in each case. The variables are

(i) grade point average in freshman year arid in sophomore )/ear (ii) grade point average in fleslunan year and in senior year (iii) length and weigl,rt of two-by.four boards

Possibievalues forthe correlation coef,ficien3 are -.50,0.0, 0.30,0.60. and 0,95. Match the conelations with the data sets.

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