spss notes onesamplef11

8/10/2019 SPSS Notes OnesampleF11

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Descriptives

1.0200 .37824

.1644

1.8756

~ ~ ~ ~

1.19610

Mean

Lower Bound

Upper Bound

95% Confidence

n!er"a# for Mean

~ ~ ~ ~ ~ ~ ~

$!d. e"ia!ion

$&''(L)$

$!a! i* !ic $!d. 'rror

One-Sample Statistics

10 1.0200 1.1961 .3782$&''(L)$ + Mean

$!d.

e"ia!ion

$!d. 'rror

Mean

One-Sample Test

2.697 9 .0245 1.0200 .1644 1.8756$&''(L)$

! df

$i,.

-2!ai#ed/

Mean

ifference Lower Upper

95% Confidence

n!er"a# of !e

ifference

(e*! a#ue 0

0: Null hypothesis value

p-value 0 (Add

0to these

to get a CI forthe meanvalue.)

Divide by 2 to get 1 tailed p value

SPSS notes, Math 151: Statistical inference (BPS5e Ch. 1! SPSSv.1"

One variable, t procedures:

One sample t testCola manufacturers test new recipes for loss of sweetness during storage. Trained testers rate the sweetness change

(before after). (Positive number indicates sweetness is lost.) Results for 0 tasters for a new cola recipe:

!oad or t"pe in the data: #.0 0.$ 0.% #.0 0.$ #.# .& .# . #.&.'Pe p. $0* eg. %.&. +ile at \\Morganstore: Users\ ssievers \Math151-Moore5e\PC-SPSS\Ch17\eg17-03.por.T"peSWEETLSin the!aria"#e !ie$: La"e#column so "our output will be labeled.

Chec, the !aria"#e !ie$: Meas%re column. -t needs to be S&a#e'

Chec, for near normalit": otplot ()raphs*Lega&+,ia#ogs*S&atter,ot*Sip#e,ot/ is / for this few.

#nal$%e&CompareMeans&One-Sample T Test.elect the variable to be tested and clic, it across to the right bo1etTest 'ale= "our H0value 2 3 0here (4no loss4).

(+or Confidence interval aroundtest value* do Options* t"pe in thedesired confidence level.)

5et the results* then e1amine the

output here66Resultsfor one

sample

t(71ample

%.& p.

$06)

To get more digits showing in a table (e.g. for sig. 3 .0#$) ouble clic, on the table* then clic, on the cell of

interest* till it8s highlighted (white on blac,). 5o to oratmenu*Ce## Properties* orat !a#%eand "ou can changenumber of decimal places. Can be cran,".

9a: 0 (positive numbers are loss in sweetness) o P6value 3 .0#$;# 3 .0#&.

Confidence Interval: (do above* with test value 3 0* /R* if "our null h"pothesis isn8t 0...)

na#ee*crip!i"e $!a!*)*plore. (Clic, "our variable into the ependen! #i*!.)-nthe 'p#ore dialog bo1* hit theStatisticsbutton: +ind the boxto change the confidence level* but leave it as ote td. 7rror .&%?#$

3 td. eviation

.


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sAuare root of 0(&.@#)

$$$no!e*one*a:p#e;11.doc 11


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Matched pairs (Paired samples) pp. $&6$%Starting it! data in to variables""a value for each measured on each subBect or pair.

('Pe p.$. 71ample %.$ o Chimpanees CollaborateD)./pen the datafile from Table %.*Math151-Moore5e\PC-SPSS\Ch17\ta17-01.por. The file doesn8t e1actl" match the table66ifferences aren8t given.

The variables are colla+andnocolla+. #$pe Collab NeededandNo Collab Neededin the!aria"#e !ie$:La"e#scolumn. Chec, the !aria"#e !ie$: Meas%re columns. The" need to be S&a#e'

na#eCo:pare Mean*Paire-Samples T-TestClic, Collab Neededacross. Then clic, No

Collab Neededacross. The one that is clic,ed across firstwill become !aria"#e1* the other will become !aria"#e * in Pair 1. The variables will be subtracted in thedirection shown, Variable 1 Variable 2, in this procedure -Co##a=+oCo##a=/ If you wanted to look at-+oCo##a=Co##a=/you could highlight their row and use the double arrow to reverse their places .o 2.

(The null h"pothesis in the P Paired amples procedure is alwaysassumed to be Eno

differenceF* the pop%lation mean of the difference= 0* so it isn8t stated. Confidence &evelisunder )p!ion*button.)

This is a one6sided testGchimps will see, a partner more when it8s needed (positive mean

difference). The t is ver" large* over %* so the P6value is ver" small (- reformatted to show more digits..P (one6sided) 3 .000&H#3.0000%%. 71tremel" highl" significant.



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Optional:

Create a ne variable !ic! !olds t!e

'ifference for eac! s%bect:

Ise (ran*for: Co:pu!e "aria=#e* then t"peand;or clic, across to get

Taret 'aria+le /meric )*pressionDifference collab nocollab .

T+peLa"e# Use e4pression as #a"e#is good. 9it)> to ma,e the new variable.

Jatched pairs test can now be done Bust using

the Differencevariable and the One-sample

method. (The cola data66front page66was differencesbefore6to6afterGthe" Bust didn8t give us the raw values.)

Kou can use the ,ieren&e variable to chec, for s,ewness* outliers. ( L Test against a non60 9o.)


spss notes onesamplef11

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