Introduction to Statistics Part A - Outputs: 1. A sample of university employees had been assembled. An output concerning their education is presented below. Study the output and answer the following questions: a. What is the mean, median and the standard deviation? b. Firstly, what is the interquartile range, and secondly, how many education years has the most educated employee? c. what is the number of education years that 36% of the sample has that number of education years or below it? Answer the same question for 83%. d. Firstly, how many employees has 12 education years or less? Secondly, how many employees have missing values in the variable education years? Statistics Highest Year of School Completed 1510 7 12.88 12.00 12 2.984 8.904 20 0 20 19455 9.00 12.00 12.00 12.00 15.00 16.00 Valid Missing N Mean Median Mode St d. Dev iation Variance Range Minimum Maxim um Sum 10 25 36 50 75 83 Percentiles 2. Researcher which studies the field of eating disorders checked the correlation between subjects body image ranking and the degree to which they restrict food intake. Study the output and answer the following questions: Highest Year of School Completed 2 .1 .1 .1 5 .3 .3 .5 5 .3 .3 .8 6 .4 .4 1.2 12 .8 .8 2.0 25 1.6 1.7 3.6 68 4.5 4.5 8.1 56 3.7 3.7 11.9 73 4.8 4.8 16.7 85 5.6 5.6 22.3 461 30.4 30.5 52.8 130 8.6 8.6 61.5 175 11.5 11.6 73.0 73 4.8 4.8 77.9 194 12.8 12.8 90.7 43 2.8 2.8 93.6 45 3.0 3.0 96.6 22 1.5 1.5 98.0 30 2.0 2.0 100.0 1510 99.5 100.0 7 .5 1517 100.0 0 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Total Valid NAMissing Total Frequency Percent Valid Percent Cumulat iv e Percent Correlati ons 1 .383** .000 217 217 .383** 1 .000 217 217 Pearson Correlation Sig. (2-tailed) N Pearson Correlation Sig. (2-tailed) N Body perception Restriction of f ood intake (f asting) Body perception Restriction of f ood intake (f asting) Correlation is signif icant at the 0.01 lev el (2-t ailed).**. 1. What can be inferred from the table? a. There is a significant negative correlation between the variables. b. There is a moderately negative correlation between the variables. c. There is a moderately positive correlation between the variables. d. There is a weak positive correlation between the variables. 2. Report the correlation. 3. The following output present a regression done in order to predict the number of SMS messages a person sends to his\hers partner by the length of the relationship (in years). Study the output and answer the following questions: Regression Model Summary Model R R Square Adjusted R Square Std. Error of the Estimate 1 -.661(a) .436 .435 123.540 a Predictors: (Constant), Duration of relationship (years) ANOVA(b) .

1. Introduction to Statistics
Part A - Outputs:
1. A sample of university employees had been assembled. An
output
concerning their education is presented below. Study the output
and
answer the following questions:
a. What is the mean, median and the standard deviation?
b. Firstly, what is the interquartile range, and secondly, how
many education years has
the most educated employee?
c. what is the number of education years that 36% of the sample
has that number of
education years or below it? Answer the same question for 83%.
d. Firstly, how many employees has 12 education years or less?
Secondly, how many
employees have missing values in the variable education years?
Statistics

2. Highest Year of School Completed
1510
7
12.88
12.00
12
2.984
8.904
20
0
20
19455
9.00
12.00
12.00
12.00
15.00
16.00

3. Valid
Missing
N
Mean
Median
Mode
St d. Dev iation
Variance
Range
Minimum
Maxim um
Sum
10
25
36
50
75
83

4. Percentiles
2. Researcher which studies the field of eating disorders
checked the
correlation between subjects body image ranking and the degree
to
which they restrict food intake. Study the output and answer the
following questions:
Highest Year of School Completed
2 .1 .1 .1
5 .3 .3 .5
5 .3 .3 .8
6 .4 .4 1.2
12 .8 .8 2.0
25 1.6 1.7 3.6
68 4.5 4.5 8.1

5. 56 3.7 3.7 11.9
73 4.8 4.8 16.7
85 5.6 5.6 22.3
461 30.4 30.5 52.8
130 8.6 8.6 61.5
175 11.5 11.6 73.0
73 4.8 4.8 77.9
194 12.8 12.8 90.7
43 2.8 2.8 93.6
45 3.0 3.0 96.6
22 1.5 1.5 98.0
30 2.0 2.0 100.0
1510 99.5 100.0
7 .5
1517 100.0
0
3
4

6. 5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Total
Valid

7. NAMissing
Total
Frequency Percent Valid Percent
Cumulat iv e
Percent
Correlati ons
1 .383**
.000
217 217
.383** 1
.000
217 217
Pearson Correlation
Sig. (2-tailed)
N
Pearson Correlation
Sig. (2-tailed)
N

8. Body perception
Restriction of f ood
intake (f asting)
Body
perception
Restriction of
f ood intake
(f asting)
Correlation is signif icant at the 0.01 lev el (2-t ailed).**.
1. What can be inferred from the table?
a. There is a significant negative correlation between the
variables.
b. There is a moderately negative correlation between the
variables.
c. There is a moderately positive correlation between the
variables.
d. There is a weak positive correlation between the variables.
2. Report the correlation.
3. The following output present a regression done in order to

9. predict
the number of SMS messages a person sends to hishers partner
by the
length of the relationship (in years). Study the output and
answer the
following questions:
Regression
Model Summary
Model R R Square
Adjusted R
Square
Std. Error of the
Estimate
1 -.661(a) .436 .435 123.540
a Predictors: (Constant), Duration of relationship (years)
ANOVA(b)
Model Sum of Squares df Mean Square F Sig.
1 Regression 6010.000 1 100.000 365.381 .000(a)

10. Residual 7776.340 472 160.840
Total 13776.340 473
a Predictors: (Constant), Duration of relationship (years)
b Dependent Variable: SMS
Coefficients(a)
Model
Unstandardized
Coefficients
Standardized
Coefficients t Sig.
B Std. Error Beta B Std. Error
1 (Constant) 15.178 2821.912 -6.496 .000
Duration of relationship
(years)
-0.183 204.547 .661 19.115 .000
a Dependent Variable: SMS

11. 1. What is the percentage of explained variance?
2. Write the regression line equation.
3. Brad and Angelina are married for 25 years. According to
this analysis, how many
SMS messages should Brad send Angelina?
4. A researcher is conducting a research on the effects of
sociability on
mood. He is using a questionnaire in order to assess sociability.
Study
the output concerning the reliability check and answer the
following
questions:
Reliability
Scale: sociability
Case Processing Summary
N %
Cases
Valid 198 99.0

12. Excludeda 2 1.0
Total 200 100.0
a. Listwise deletion based on all variables in the
procedure.
Reliability Statistics
Cronbach's Alpha
Cronbach's Alpha
Based on
Standardized Items
N of Items
.627 .659 8
Inter-Item Correlation Matrix
1 2 3 4 5 6 7 8
1. I like to see friends 1.000 .605 -.024 .189 .501 -.435 .451
.396
2. I talk a lot with friends on the phone .605 1.000 -.001 .362

13. .492 -.837 .509 .424
3. I like chocolate -.024 -.001 1.000 .003 .009 .001 -.001 -.017
4. I go to a lot of parties .189 .362 .003 1.000 .408 -.557 .430
.411
5. I have many friends .501 .492 .009 .408 1.000 -.243 .675 .510
6. I like to read alone at home -.435 -.837 .001 -.557 -.243
1.000 -.408 -.650
7. Romantic relationship are important .451 .509 -.001 .430 .675
-.408 1.000 .495
8. I feel good with my social status .396 .424 -.017 .411 .510 -
.650 .495 1.000
Item-Total Statistics
Scale Mean if
Item Deleted
Scale Variance if
Item Deleted
Corrected Item-

14. Total Correlation
Squared Multiple
Correlation
Cronbach's Alpha
if Item Deleted
1. I like to see friends 17.4495 26.188 .515 .443 .561
2. I talk a lot with friends on
the phone
17.2374 24.009 .555 .472 .534
3. I like chocolate 16.1919 29.811 .007 .018 .686
4. I go to a lot of parties 15.9697 23.826 .399 .330 .571
5. I have many friends 16.7273 21.753 .666 .546 .489
6. I like to read alone at home 14.6768 35.540 -.320 .196 .753
7. Romantic relationship are
important
17.0556 23.220 .634 .528 .512
8. I feel good with my social
status
16.4192 23.260 .473 .397 .547

15. 1. What is the number of subjects who's answers had been
entered to the reliability
check?
2. What is the internal reliability of the sociability
questionnaire?
3. which item (or items) would you suggest to change or omit
(leave out)? explain why,
both from a statistical point of view and from the theoretical
point of view.
Part B - statistical comprehension:
1. Study the table and answer the following questions:
Taken from Somer, E., Maguen, S., Or-Chen, K. & Litz, B.
(2008). Managing Terror:
Differences between Jews and Arabs in Israel. International
Journal of
Psychology, 42, 1-9.
Table 1
Demographic Variables of Jewish-Israelis and Arab-Israelis

16. Demographic
Characteristics
Jewish-
Israelis
(n = 100)
Arab-
Israelis
(n = 100)
Statistic comparing the
two groups
Age (years)
M = 43.60
(SD =
16.76)
M = 36.62
(SD=13.02)
t(198) = 10.82**

17. Gender
Male
Female
24%
76%
34%
66%
Marital status
Married
Non-Married
60%
40%
73%
27%

18. Religion
Jewish
Christian
Muslim
Druze
100%
0%
0%
0%
0%
72%
27%
1%

19. Table 1
Demographic Variables of Jewish-Israelis and Arab-Israelis
Demographic
Characteristics
Jewish-
Israelis
(n = 100)
Arab-
Israelis
(n = 100)
Statistic comparing the
two groups
Religiosity
Religious
laroitidarT
raluTra
%10

20. %26
%64
%18
%58
%24
ecalphtriB
learaT
Other
%60
%40
%99
%1

21. *p<0.05
**p<0.01
1. What is the conclusion from the results of the test done
between nationality and age
? Did a significant correlation had been found? Which test did
the researchers use?
2. The Pearson correlation between all the of the research
variables is displayed in the
following table. Please report (in length) what is the most
important correlation.
explain why.
Table 2
Correlations Among Variables in Regression Models
Variable 1 2 3 4 5 6 7 8 9 10
1. PTSD --
2. Depression .77** --
3. Somatization .58** .66** --
4. Group -.38** -.46 ** -.04 --

22. 5. Age .03 -.03 .19** .23** --
6. Gender .21** .23** .20** .11 .05 --
7. Education -.22** -.23** -.27** .16* .06 -.05 --
8. Religiosity -.20** -.21** -.09 .34** .10 -.03 -.26** --
9. Marriage -.13 -.12 -.09 .14 -.47** -.04 .05 .15* --
10. Birthplace -.15 -.21** .02 .48** .45** .11 .08 .19** -.07 --
*p<0.05
**p<0.01
Good luck!