1. A study from the late 1990s reported that the mean reading speed for students in university was 262 syllables per minute (SPM). Due to the increased use of multimedia and smartphones, a group of researchers predicted that the mean reading speed for university students has decreased. To test this claim, the researchers recruited 50 university students and measured their reading speeds. Which hypothesis test should be used? Group of answer choices None of the tests listed are appropriate 1-sample t-test 2-sample independent t-test 2-sample paired t-test 2. It is claimed that occupational health and safety programsreducethe loss of working hours due to accidents. To test this claim, 15 industrial plants collected data about the weekly loss of working hours due to accidents both before and after an occupational health and safety program was implemented. Which hypothesis test should be used? Group of answer choices 2-sample paired t-test 2-sample independent t-test 1-sample t-test None of the hypothesis tests are appropriate 3. A researcher was interested in examining running performance under different environmental conditions. Ten athletes were recruited and asked to run 200 metres in each of the four different weather conditions: heat, rain, wind, snow. The research question was: is there a difference in running time across the four weather conditions? Which hypothesis test should be used to answer this question? Group of answer choices 2-sample paired t-test 1-sample t-test None of the tests listed are appropriate 2-sample independent t-test 4. A study was conducted on the fine motor skills of 12 kindergarten children undergoing occupational therapy. An index was used to measure the hand use, hand-eye coordination, and manual dexterity of the children before the therapy began and then again after seven months of therapy. The aim of the study was to determine if occupational therapy affected the index score. The data were analysed and the results are presented below.

Test statistics
t	df	1-sided p-value	2-sided p-value	Mean Difference
2.352	17	0.0155	0.031	7.72

Using a 1% level of significance, fill in the blanks to make your statistical decision and conclusion. ["", ""] the ["", ""]hypothesis as the p-value is ["", ""]than the alpha value. Thus, there is ["", ""]evidence to suggest a mean difference, t(17)=2.352,p=0.031. 5. A study from the late 1990s reported that the mean reading speed for students in university was 262 syllables per minute (SPM). Due to increased use of multimedia and smartphones, a group of researchers predicted that the mean reading speed for university students hasdecreased. To test this claim, the researchers recruited 50 university students and measured their reading speeds. The data collected were analysed with SPSS and the corresponding SPSS output is shown below.

Statistics
t	df	1-sidedp-value	2-sidedp-value	Mean Difference	95% CI Lower Bound	95% CI Upper Bound
-2.519	49	0.0075	0.015	-17.26	-31.03	-3.49

What is thep-value that resulted from this statistical analysis? Enter your answer as an exact value. 6. A pharmaceutical company wants to determine if the time from ingestion to headache reliefdiffersbetween the tablet form and liquid capsule form of an analgesic drug (i.e. painkiller). To study this, the research team gave 24 participants the tablet form of the drug and 22 different participants the liquid capsule form of the drug. The amount of time (minutes) to pain relief was then recorded.

Test Statistics
Independent Samples Test
	Levene's Test for Equality of Variances	t-test for Equality of Means
F	Sig.	t	df	Significance	Mean Difference	Std. Error Difference	95% Confidence Interval of the Difference
One-Sided p	Two-Sided p	Lower	Upper
Time to Pain Relief (min)	Equal variances assumed	.065	.799	2.794	44	0.004	0.008	5.72	2.05	1.59	9.84
Equal variances not assumed			2.808	43.984	0.0035	0.007	5.72	2.04	1.61	9.82

Using the statistics table above, what is the resulting p-value of this study? 7. FEV1 (the amount of air that is expelled from the lungs in 1 second) is one measure of lung function. The higher the FEV1, the better the lung function. It is thought that smoking cessation (i.e. stopping smoking) can improve lung function. To determine whether this is true, a research group recruited 25 smokers who wanted to quit smoking. Their FEV1 was measured upon recruitment and again 6 months post-cessation. What are the competing hypothesis statements for this test? Group of answer choices H0:Before=After H1:BeforeH0:D=0, whereD=After-Before H1:D>0 H0:D=0, whereD=After-Before H1:D?0 H0:D=0, whereD=After-Before H1:DH0:D>0, whereD=After-Before H1:D=0 8. A study was conducted to determine whether there is a mean difference in body mass index (BMI) between non-vegetarians and vegetarians. To conduct this study, 24 non-vegetarians and 22 vegetarians were recruited and their BMI was measured on their baseline visit. Before conducting the statistical analyses, the researchers performed exploratory data analysis to check for outliers and normality. Based on the results below, which t-test assumptions are violated, if any?

Test statistics
Tests of Normality
	Diet	Kolmogorov-Smirnova	Shapiro-Wilk
	Statistic	df	Sig.	Statistic	df	Sig.
BMI (kg/m2)	Non-Vegetarian	.121	24	.200*	.868	24	.005
Vegetarian	.148	22	.200*	.936	22	.164
*. This is a lower bound of the true significance.
Lilliefors Significance Correction

Group of answer choices Only no extreme outliers is violated No assumptions are violated Both assumptions (no extreme outliers and normality) are violated Only normality is violated 9. Arsenic is a natural chemical element that is found in the soil, air, and water (including drinking water). Arsenic is also produced during industrial processes, which can lead to arsenic pollution. If arsenic levels become too high in drinking water, it can lead to arsenic poisoning. A local city council wanted to assess arsenic levels in industrial and non-industrial areas to determine risks of arsenic poisoning. They sampled ground water from 8 industrial sites and 14 non-industrial sites, and measured the arsenic levels. The 99% confidence intervals of the means were calculated to be: Industrial (9.4,16.1) Non-industrial (4.6,8.9) Usinga=0.01and based on the information provided, make a statistical decision. Group of answer choices Reject the null hypothesis Do not reject the null hypothesis There is not enough information provided

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