This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.
View Full Document
Unformatted text preview: EC 41 UCLA  — Sample Problems #1; RE Ch 1 material
These problems will NOT be collected or graded, but they will be useful for studying for exams. I) Let x be the income (in thousands ofS) for households in a US. neighborhood Suppose 10 households are sampled and the
values forx are: 15, 35, 45, IO, 40, 35, IO, 15, I5, 50 a) Write :1 stemplot ofthis data: b) Write two histograms below with either counts or percent on the vertical axis. i) To the left make a histogram such that OlO includes 10 but not 0, 1020 includes 20 but not 10... (Excel will construct such a
histogrzun if“hin entries“ are 10,20,30,40,50) ii) To the right make a histogram such that 0IO includes 0 but not I0, l020 includes 10 but not 20... Which way does 0111' text use for drawing histograms.)
//'; 0 IO 20 30 40 SO 60 Income 0 10 20 30 40 50 Income \ Htﬁt’ftlbld’n 0C) 2) Let x be the income (in Yen) for households in a Japanese neighborhood. Suppose 9 households are sampled and the values
for x are: 2000, 3500. 4000, 2500. 4000, 3500, 1500, 2500, 4:300 ft? ’20 :33: ‘21: 3c 7, s” W W L/S‘ us. Suppose one US. $ —~ I00 Yen. Convert Japanese earnings 8' S' Q" 0 l  I;
and make a backtoback stem plot using data from #1 and #2. ._ _ — — ——  —— "H ‘
2 0 4: S
b) What is the average (—' arithmetic mean) income ofthe a __
Japanese households in Yen and in S"? _ ,2) I I try‘3" 3 5 5 Kimmie  — ' H c) Compare the lQR for Japanese and U.S. household incomes. .. ._.. —
(measure both in S) 5. Us; TEXT r1121 rift“3. 3) Consider the ten household incomes from #1: IS, 35, 45, IO, 40, 35, IO, 15, 15,50. / y,
Z I a) What is the average (arithmetic mean) income (in thousands) for the 10 observations? _ m d 2 / ‘— X
b) What is the standard deviation ofthese l0 values? l ‘5. ST . . /V
c) What is the variance ofthese 10 values? ” 0
Follow the text and use “sample” not “population” values for standard deviation and variance unless instructed to do otherwise. d) Use the data from question #1 to perform a “ﬁve number summary," )3)» )ﬂ / P {g 2. q. 3. S.“ :57 5\ [/ﬂ (a... (\0 Minimum Value: /0 . ._ First Quartile, Q]: If?) ‘3 U .w
,s mt 36‘ z 1
Median: ’2 (e. : l ' "t P H0
Third Quartile, Q3. 1H) ’5 6"
J 2 8—
, ' . h‘ ‘6 Maximum Value. 0 _ I 0 ,_ I”; e) To the right make a boxplot with “whiskers” extending, to max and min values What is the inter uartile ranoe'.’ .‘~ \ "
0 q t? L Griz — 4) Consider the data on luck and children’s scores (from  to 10) for problem 1.60 on page 49. . . . « 5' 7 l
b) What IS the (sample) standard devralten? x“ f l ‘ I
. . . it 2 ‘ 9  ' . c) What IS the variance? _ 1:2 ‘ ~ ‘.  a; .. _. t
 realize we follow the text and use “sample” standard deviation, not “population” ‘I I " ' _ h I. ,
 you may use a your calculator or Excel to answer questiOn 4 and 5. ' 1 n
5) Use the data from question #4 to perform a “ﬁve number summary”
and write a boxplot as described on pages 37 & 38
i k'l T»— '
Minimle Value: \ '
First Quartile, Q.: l ‘
. t  /
Median: {9. l
‘ ' '"S
  .9" t r
Third Quartile. Q3 1“] a t
.. I
1 F
Maximum Value. JU '
What is one aspect ofthe data that the boxplot and sumnun'y statisties can not show? . l". .
{ft ...
View Full
Document
 Spring '07
 Guggenberger

Click to edit the document details