1.Suppose you have information that the mean weight of all female employees (N= 450) in a manufacturing industry is 120 pounds and the standard deviation of the weights is 8 pounds.

Use the Chebyshev rule to formulate two statements mentioning the number of female employees and the interval containing at least 75%and 89% of all the measures in the population.

Statement 1___________________________________________________

_____________________________________________________________

Statement 2___________________________________________________

_____________________________________________________________

Inferential Statistics

1.ESTIMATES. A recent study reported that an estimated 70% of professionals in Occupational Therapy have considered moving to the US to earn a higher salary.The report further stated that this estimate is considered accurate within the three percentage points, and correct 19 times out of 20.

a.Interpret the 70%. Is it the parameter or statistic?

b.What is the meaning of "within 3%" ?

c.Explain what the phrase "19 out of 20" means.

d.Identify the lower and upper bounds of the interval estimate for the parameter.

e.Give your interpretation.

2.Consider the processed data below.(Paired t-test)

a.State the null hypothesis.______________________________________________

b.What is the difference between the pretest and posttest scores?_________________

c.At 5 % level of significance, is the difference between the means significant or not based on the process data below?____________

d.What is the decision? (Reject H₀or Do not reject H₀?________________

e.State your conclusion._____________________________________________

Paired Samples Statistics

Mean

N

Std. Deviation

Std. Error Mean

Pair 1

pretest scores

19.95

98

3.329

.336

posttest scores

28.68

98

1.577

.159

Paired Samples Test

Paired Differences

t

df

Sig. (2-tailed)

Mean

Std. Deviation

Std. Error Mean

95% Confidence Interval of the Difference

Lower

Upper

Pair 1

pretest scores - posttest scores

-8.735

3.241

.327

-9.385

-8.085

-26.677

97

.000

3.ANOVA.Using the post hoc test, and the mean values of the scores in :

Method 1 (lecture only): mean score = 26.5

Method 2 (lecture & reading: mean score = 33.5

Method 3 (lecture & film showing: mean score = 36.4

At 5 % level of significance, determine each statement if it is TRUE or FALSE.

_________There is no significant difference between the three methods.

_________Method 2 is more effective than method 1.

_________Method 3 is more effective than method 2.

_________Method 3 is more effective than method 1.

__________The null hypothesis is accepted.

ANOVA

Scores

Sum of Squares

df

Mean Square

F

Sig.

Between Groups

518.067

2

259.033

4.179

.026

Within Groups

1673.400

27

61.978

Total

2191.467

29

Post Hoc Tests

Multiple Comparisons

Dependent Variable: Scores

LSD

(I) Methods

(J) Methods

Mean Difference (I-J)

Std. Error

Sig.

95% Confidence Interval

Lower Bound

Upper Bound

lecture only

lecture & reading

-7.000

3.521

.057

-14.22

.22

lecture & film showing

-9.900^*

3.521

.009

-17.12

-2.68

lecture & reading

lecture only

7.000

3.521

.057

-.22

14.22

lecture & film showing

-2.900

3.521

.417

-10.12

4.32

lecture & film showing

lecture only

9.900^*

3.521

.009

2.68

17.12

lecture & reading

2.900

3.521

.417

-4.32

10.12

*. The mean difference is significant at the 0.05 level.