PLEASE SHOW ILLUSTRATIONS AND COMPUTATION PLEASE ! PLEASE ! PLEASE!

1)It is known that a particular laboratory task takes the average person 2.5 seconds. A researcher was interested in whether older people are slower (take longer) on this task. The researcher tested 30 randomly selected 80-year-olds. Their mean time was 2.7 seconds, with an estimated population standard deviation of 1.4 seconds. What should the researcher conclude (use the .05 level)?

a./2 Identify the populations involved: population 1 = _____________________________________________________________________ population 2 = _____________________________________________________________________

b. /2 State the research and null hypothesis: Research Hypothesis = _____________________________________________________________ Null Hypothesis = _________________________________________________________________

c. /6 Determine the characteristics of the comparison distribution (hint: it is a distribution of means):

mean of the distribution of means = degrees of freedom = estimated population variance = estimated population standard deviation = variance of the distribution of means = standard deviation of distribution of means =

d. /1 Cutoff sample score on the comparison distribution at which we'll reject H₀ (hint: 1 or 2 tails?) =

e. /1 Determine your sample's score on the comparison distribution =

f. /1 Accept or reject the null hypothesis?

g. /4 Sketch the distributions involved:

2) An organizational specialist is hired as a consultant to a company planning to open a coffee house for college students. The company wants to know if the customers will drink more or less coffee if the coffee house is decorated in a Paris motif or in a San Francisco motif. To test this, the researcher sets up two similar rooms, but with the two different motifs. She then arranges to have eight students spend an afternoon in each room while being allowed to drink all the coffee they like. (The order in which they sit in the rooms is rotated, so that half do their first afternoon in the Paris room and half in the San Francisco room.) The amount each student drinks is recorded below:

Cups of Coffee Consumed for each Motif

Participant	Paris	San Francisco
A	8.5	8.4
B	4.3	4.6
C	2.0	1.7
D	7.8	7.3
E	7.0	7.2
F	9.1	7.4
G	3.3	3.0
H	3.5	3.5

Is there is' a significant difference between the number of cups of coffee consumed in the two rooms (use the .05 level)?

a./2 Identify the populations involved: population 1 = _____________________________________________________________________ population 2 = _____________________________________________________________________

b. /2 State the research and null hypothesis: Research Hypothesis = _____________________________________________________________ Null Hypothesis = _________________________________________________________________

c. /7 Determine the characteristics of the comparison distribution (hint: it is a distribution of means): mean of the comparison population's difference scores = sample's difference scores (San Fran - Paris) = degrees of freedom = estimated variance of the comparison population's difference scores = estimated standard deviation of the comparison population's difference scores = variance of the distribution of means = standard deviation of distribution of means =

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2.d. /1 Cutoff sample score on the comparison distribution at which we'll reject H0 (hint: 1 or 2 tails?) =

2 e. /1 Determine your sample's score on the comparison distribution =

f. /1 Accept or reject the null hypothesis?

3. Describe a hypothetical scenario in which you would use a t testfor a) a single sample and b) dependent means to analyze the results of a research study:

1. /2 Scenario: /1 Population 1: _______________________________________________________________________ /1 Population 2: _______________________________________________________________________ /1 Research hypothesis: _________________________________________________________________ /1 Null hypothesis: _____________________________________________________________________

1. /2 Scenario: /1 Population 1: _______________________________________________________________________ /1 Population 2: _______________________________________________________________________ /1 Research hypothesis: _________________________________________________________________ /1 Null hypothesis: _____________________________________________________________________