# Week 2 & 3 Assignment – basic BioStatistics

**14 + 8 Answers and calculations as basic statistics tyro would clear-up put into twain an MS Excel spreadsheet and copied into MS Word doc format. Due by 7pm 2/2/14. **

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**Week 2 Assignment**

- A. What is the presumption of rolling a immodest in the gambling dice frolic of craps (loving two six sided dice)?

B. What is the presumption that a player can roll a immodest 3 eras in a row (presume that rolling the dice each era does not pretend the remainder of the proximate roll)?

- Population A and Population B twain possess a moderation culmination of 70.0 inches subjoined a while an SD of 6.0. A accidental specimen of 30 crowd is fine from population A, and accidental specimen of 50 crowd is selected from Population B. Which specimen moderation earn probably let-go a past accurebuke deem of its population moderation? Why?

3. Suppose we obtained columnulates on humor bulk subjoined contact of a nitroglycerin ointment in a specimen of 50 resigneds. The moderation humor bulk is set-up to be 7.8mm subjoined a while an SD of 2.1. Using a *t* arrangement consideration, what are the faith limits for a 95% faith period? For a 99% faith period?

4. In a guide con-over evaluating the use of a new offal to inferior relying core rebukes (HR) of resigneds, the subjoined columnulates was narrative:

**Subject #**

**Resting HR**

001

72

002

88

003

71

004

87

005

64

006

77

007

79

008

59

009

66

010

68

011

78

012

89

013

91

014

81

015

77

016

75

017

69

Given that the medium relying HR of the unconcealed population for this con-over is 72, use StatCrunch to fulfil the misspend *t* standard. What is the prize of *t*? Using an alpha of 0.05, is the *t* statistic speaking? Why? What are the faith limits for a 95% faith period hither and what do they moderation for this resigned cluster? Copy and Paste your operation from StatCrunch into your Word muniment patience.

5. Write one or two sentences that could be used to recital the results obtained for the t-standard in Employment 4.

6. For which of the subjoined situations is the **independent** clusters t-standard misspend (if impertinent, why?):

a. The stubborn capricious is infant rise importance at one week (natural vs haughty); the contingent capricious is relying core rebuke.

b. The stubborn capricious is radiation texture on throat cancer resigneds (subjoined a low dose and then a haughty dose texture); the contingent capricious is unspotted order cell reckon.

c. The IV is infant rise importance (low vs natural rise importance); the DV is estimate of days listless from initiate in primitive gait.

d. The IV is gender (manly vs effeminate); the DV is obedience vs nonobedience subjoined a while a medication sustenance.

e. The stubborn capricious is married foothold (uncompounded vs divorced vs married); the contingent capricious is enjoyment measured on a flake from 1 to 50

7. For which of the subjoined situations is the **dependent** clusters t-standard misspend (if not misspend, why?)

a. The IV is intercourse or scantiness of chat directed to sleepy resigneds (identical resigneds subjoined a while and subjoined a whileout chat); the DV is the resigneds’ intracranial hurry.

b. The IV is rise character (residence vs hospital); the DV is perceived functional force of the resigned 48 hours subjoined surgery.

c. The IV is era since subjection (1 months vs 3 months vs 6 months); the DV is matter importance.

d. The IV is menopausal avow (pre vs column); the DV is attitudes inland menopause.

e. The IV is nap therapy for narcoleptics (identical resigneds precedently vs subjoined texture); the DV is the character of nap they had the subjoined week (had unplanned vs didn’t possess unplanned nap).

8. Suppose we wanted to standard the supposition that a administer cluster of cancer resigneds (Group 1) would recital haughtyer moderation self-denial ratings than an experimental cluster receiving distinctive massage textures (Group 2). Use the subjoined advice. Appraise a *t*-statistic for stubborn clusters:

moderation cluster 1 = 78.1 SD^{2}_{1} = 42.1 n_{1} = 25

moderation cluster 2 = 75.1 SD^{2}_{2} = 39.7 n_{2}=25

What are the degrees of insubservience and the prize of* t* ? Using α=0.05 for a two-tailed standard, is this *t* statistic speaking? Show your calculations (or StatCrunch output) for ample trustworthiness.

9. Write one or two sentences that could be used to recital the results obtained for the t-standard in Employment 8.

10. For each of the subjoined t prizes, declare whether the *t *is statistically speaking for a two-tailed standard, at the restricted alphas:

a. *t* = 2.90, *df* = 25, α = 0.01

b. *t* = 2.00, *dr* = 25, α = 0.05

c. *t *= 5.52, *df *= 10, α = 0.01

d. *t *= 2.02, *df *= 150, α = 0.05

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11. For each of the subjoined situations, declare whether ANOVA is misspend; if not misspend, the deduce why not; and, if misspend, the character of ANOVA that would be used (i.e., one-way, numerous measures, etc.)

a. The IVs are ethnicity (Asian, White, African American, Hispanic) and gender (manly vs effeminate); the DV is serum cholesterol rolls.

b. The IV is smoking foothold – smokers vs non-smokers; the DV is health-related hardiness as measured on a 20-item flake.

c. The IV is affectionate confront sustentation foothold (breastfeeds daily vs confrontfeeds at averageest 1-3 eras/week vs doesn’t confrontfeed); the DV is affectionate bonding subjoined a while infant, as measured on a 20-item self-recital flake.

d. The IV is texture cluster for resigneds subjoined a while offal-induced shaking (end wraps vs haughty space temp vs natural space temp subjoined a whileout wraps) identical resigned used for each texture; the DV is myocardial oxygen waste, measured precedently and subjoined texture.

e. The IV is tediousness of gestation (preorder vs order vs columnterm); the DV is bestowal character (vaginal vs Caesarean).

12. Suppose we wanted to assimilate the somatic complaints (as measured on a flake public as the Physical Symptom Flake or PSS) of three clusters of crowd: non-smokers, smokers, and crowd who recently depart-from smoking. Using the subjoined columnulates for PSS, do a one-way ANOVA to standard the supposition that the population moderations are equal:

Nonsmokers Smokers Quitters

19 31 30

28 29 22

17 22 23

20 24 22

25 19 17

Using StatCrunch, detail the moderations for the three clusters and appraise the sums of squares, degrees of insubservience, and moderation squares for these columnulates. What is the prize of F? Using an alpha of 0.05, is the F statistic speaking? Why? Copy and Paste your operation from StatCrunch into your Word muniment patience.

13. A new motorcycle is substance plain to unite new gas mileage standards recently passed by the federal legislation. An engineer standarded three mould artfulnesss by accidentally assigning the motorcycles in a depraved con-over (the riders narrative the mileage but did not apprehend the artfulness of the motorcycle, solely its statute). The columnulates in miles per gallon (MPG) for the three artfulnesss is listed below:

**X-1**

**B-1**

**Z-1**

45

55

54

62

55

52

50

54

41

65

44

35

62

52

38

50

69

41

50

58

51

58

45

44

Using StatCrunch, detail the moderations for the three clusters and appraise the sums of squares, degrees of insubservience, and moderation squares for these columnulates. What are the hypotheses to be standarded hither? What is the prize of *F*? Using an alpha of 0.05, is the *F* statistic speaking? Why? Copy and Paste your operation from StatCrunch into your Word muniment patience for ample trustworthiness.

14. For each of the subjoined *F* prizes, declare whether the *F* is statistically speaking at the restricted alpha roll:

a. F = 4.80, df = 4, 40 α = 0.01

b. F = 5.02, df = 3, 60, α = 0.001

c. F = 3.45, df = 3, 27, α = 0.05

d. F = 4.99, df = 2, 150, α = 0.01

e. F = 2.09, df = 2, 250, α = 0.05

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Week 3 Assignment

1. Using StatCrunch, rate the chi-square statistic and degrees of insubservience for the subjoined set of columnulates for 300 crowd:

*Group A Group B Group C Total*

Had flu shot 20 30 32 82

Didn’t possess flu shot 80 70 68 218

Total 100 100 100 300

Is the prize of the chi-square statistically speaking at the 0.05 roll?

2. Write a chapter summarizing the results of the separation in Employment 1.

3. Using StatCrunch, rate the chi-square statistic and degrees of insubservience for the subjoined set of columnulates for 180 crowd undergoing a articulation restitution texture subjoined a while a offal supplement:

*Treatment subjoined a while offal X Treatment subjoined a whileout Offal X Total*

Had > 8 wk rehab 18 32 50

Had < 8 wk rehab 70 60 130

Total 88 92 180

Is the prize of the chi-square statistically speaking at the 0.05 roll?

4. Write a chapter summarizing the results of the separation in Employment 3.

5. Loving each of the subjoined plight, detail whether the rated prizes of chi-square are statistically speaking:

a. χ^{2} = 3.02, *df* = 1, α = 0.05

b. χ^{2} = 8.09, *df* = 4, α = 0.05

c. χ^{2} = 10.67, *df* = 3, α = 0.01

d. χ^{2} = 9.88, *df* = 2, α = 0.01

6. Match each of the nonparametric standards in Column A subjoined a while its parametric reckonerpart in Column B

A. Nonparametric Test B. Parametric Test

1. Mann-Whitney *U*-test a. Paired *t*-test

2. Friedman standard b. One-way ANOVA

3. Kruskall-Wallis standard c. Stubborn clusters *t*-test

4. Wilcoxon signed-ranks standard d. Numerous measures ANOVA

7. Using the advice supposing, declare which statistical standard you opine should be used for each of the subjoined situations:

a. Incontingent capricious: natural rise importance vs. low rise importance infants; contingent capricious: 1 diminutive Apgar scores (1-10 flake).

b. Incontingent capricious: era of extent (before, during, and subjoined surgery); contingent capricious: core rebuke.

c. Incontingent capricious: era of extent (before, during, and subjoined intercession); contingent capricious: did vs did not employment frequently.

d. Incontingent capricious: barrenness texture A vs barrenness texture B vs administer condition; contingent capricious: did vs did not beseem fraught.

8. Below are three sets of **expected** frequencies for the immodest cells of **2 X 2 **contingency considerations. Identify which statistical proceeding would be misspend for each, using the most unsuppressed admission.

a. 4 4 b. 35 35 c. 9 9

21 21 65 65 91 91