Biostatistics: Exam Answer

Q1: The characteristic that takes different values on different items is called (B) the variable. (C) the variance (A) the statistie. Q2: The sex of a new-born baby is a variable. (One mark) (A) quantitative. Q3: Frequency polygon and can be drawn on the same graph. (One mark) (A) pie chart (B) non-binary. (B) histogram (C) cualitative (One mark) (D) None of them. (D) None of them. Q4: Sturges's formula is used to obtain the (One mark) (C) bar chart. (D) None of them. ((A) number of classes) (B) range of the variable. (C) width of the class. (D) None of them. Q5: The arithmetic mean of the data in a frequency table is (a/an) (A) ungrouped mean. ( B) weighted mean. (One mark) (C) both of thei (D) None of them. 06: Any subset from the set of all possible outcomes of a random experiment is...... (One mark) (A) an event (D) None of them (C) a probability. (B) a sample space. Q7: The variance of the sample mean, when selecting all possible samples of size n from a population of size N without replacement is ..... (One mark) (A) (A) type I error (B) N-1 (C) (D) None of them. .(One mark) (D) None of them. (One mark) Q9: The probability of rejecting the null hypothesis when in fact it is false is the Q8: The probability of rejecting the null hypothesis when in fact it is correct is the (B) level of significance. (C) power of test. (B) level of significance. (C) power of test. (A) type II error Q10: The power and direction of the relation between variables is measured using.......... (One mark) (D) None of therm (B) coefficient of correlation. (C) both of them. (A) regression (D) None of them. Q11: To test the hypothesis concerning the means of more than two independent populations..........is to be used. (One mark) (A) ANOVA (B) test of independence. (C) regression (D) None of them. Page 2 from 6 •For the following set data 125, 9.4, 1.5, 6.0, 7.8, 25.3, 11.1, 18.4- Q12 The man (Our mark) (A) 144 (C) 10:25 (D) Nate of them Q13 The mean is (One mark) (B) 104 (C) 94 (D) None of them Q14. The standard deviation in (Two marks) (A) 30.1514 OD 70813 (C) 5,0983 (D) None of them 015: The coefficient of variation is (One mark) (A) 42.68% (B) 16.59% (C) 60.27% (D) None of them The frequency distribution of the ages of a sample of patients visiting a certain clinic is given as follows Ac 0-9 Frequency 10-19 20-29 30-39 40-49 50-59 60-69 70-74 Em -58522 Q16: The variable to be studied is the of the patients (One mark) (A) number. (B) ages. Q17: The sample size is....... (One mark) (A) 48 (B) 79 (C) number & ages (C) 24 Q18: The mean of the distribution is (One mark) (A) 6.0 (B) 18.5570 (D) None of them (D) None of them. (C) 30.5417 (D) None of them, Q19: The standard deviation of the ages is (Two marks) (A) 17.1029 (B) 292 5089 Q20: The modal age is....... (Two marks) (A) 10.0 (B) 15.6538 Q21: The median is.......... (Two marks) (A) 30 409 (C) 1244.499 (D) None of them. (C) 35.2143 (D) None of them (B) 39.5005 (C) 34.0903 (D) None of them Tape from 6 IP(G) and PYGM 0.8 then 22: P(M) 0.2 if and only if G and Mare (One mark) (A) independent Q23:17 PM)-8.5, then Gand M (B) mutually exch (D) of them (One mark) (C) emmonal (D) Nonethein (A) independint (1) mutually exclusive Q24: PYG/M)-0.4, then P(M) cquals (One mark) (A) 0.25 (B) 0.5 (C) 0:3113 (D) None of them C ( 07)7(0.3): X-OL-8 IPX-x) 0 Otherwise 025: The mean and the standard deviation of X are respectively. (Two marka) (A) 24 and 1.68 (B) 56 and 1.2961 (C) 2.4 and 12961 (D) None of them. Q26: The probability that X exceeds 6 is (Two marks) (A) 0.9987 (B) 0.0592 (C) 0.0013 (D) None of them. If Y is a random variable following Poisson distribution | Y-P(2) | such that: P(Y-1) 3P(Y=0), then: Q27: The mean and the standard deviation of Y are......... respectively. (Two marks) (A) 3 and 3 (B) 3 and 1.732 (C) 1.732 and 3 (D) None of them. Q28: The probability that Y lies in the interval [4, 7) is (Two marks) (A) 0.1513 (B) 0.2111 (C) 0.3409 (D) None of them • A medical researcher is studying the serum bilirubin level of patients suffering from hepatitis under treatment in a certain hospital, a random sample of 10 patients was drawn from these patients yielded the following results for the variable under consideration: 14.8 20.5 12.7 21.3 15.2 26.6 22.9 23.4 19.2 15.7 Assuming normality of the population (the serum bilirubin level X): Fape 4 from 02%, if the sesoncher was stmod hypotheses will be (O) (C16 (Dy Neof 030: To test the previous hypotheos at ans, the tubideet vahend the stati ar respectivch (Twe markتخ (A) 1833.22711 (B) 1645,100 Q31: The orrect decision will be (One marki (A) Rejecting H. and cewetading that the pepolation mean is greater thes 16 (B) Acceping any conciding that the population mano less than to (C) Rejecting H, and coinclisding that the population mean is greater than 16 (D) None of them Q32: If the researcher wants to estimate the mean of the population serum blir level, dun the 99% confidence interval of the population mean will be (Two marks) (A) (14.6085 $23.85151 (B) (14.72375217763) (C) (15.2185με≤23.2415) (D) None of them To study the relationship between smoking and suffering from asthma ina population of men, a random sample of 229 men yielded the following results Suffering from asthma Present Absent Smoking Smokers 57 41 Non-smokers 30 101 Q33: The appropriate hypotheses will be (One mark) (A) He There is a relationship between smoking and suffering from asthosa H: There is no relationship between smoking and suffering from asthma (B) H: Suffering from asthma is caused by smoking H: Suffering from asthma is not caused by smoking. (C) H: Suffering from asthma and smoking are not related H: Suffering from asthma and smoking are related (D) None of them. Page 5 from 6 034: The tabulated value to test the previous hypotheses at a-0.01 is (A) 6.64 (B) 271 (C) 233 (One mark) (D) None of them Q35: The observed value computed from the sample information for the test statistic is (Two marks) (A) 654-10 (B) 29.3004 (C) 0.1290 (D) None of them Q36: The correct decision will be (Two marks) (A) Rejecting He and concluding that there is a relationship between suffering from asthma and smoking (B) Accepting He and concluding that there is no relationship between suffering from asthina and smoking (C) Rejecting He and concluding that there is no relationship between suffering from asthina and smoking. (D) None of them. The following ANOVA table is constructed to test if there is a significant differences between the effects of three drugs on headache at (a -0.05) S.O. V. Among drugs Within drugs SSB SSW Total 193.6 12 MS 49.4 MSW Q37: The values of SSB, SSW, dy(B), df(T), AISW, and Foare respectively. (Three marks) (A) 1482, 45.4, 3, 15, 3:783, and 5.625 (C) 98.8.94.8, 2. 14, 7.9, and 6.253 (B) 51.4, 1422, 2, 14, 185, and 4.160 (D) None of them Q38: The appropriate hypotheses will be ........ (One mark) (A) Ho There is no relationship between the effects of the drugs on headache H₁: There is a relationship between the effects of the drugs on headache (B) He: There is no significant differences between the effects of the drugs on headache H: One drog at least has a different effect on headache (C) Ho: The effects of the drugs on headache are significantly not the same H: The effects of the drugs on headache are significantly the same (D) None of them. Page 6 from f 039. The tabuland value to test the previttus hypotheses (One marka) (A) 281 (B) 3.30 Q40: The correct decision will be. (C) 349 (One mark) (D) Nine of then (A) Rejecting Hand conchualing that there is no relationship between the effects of the drugs (B) Accepting H, and say that there is no significant differences between the effects of th (C) Rejecting Hoand concluding that the effects of the drugs on headache are not the same (D) None of them The following are paired measurements of two variables named X and Y X Y 9 5. 2 14 10 Q41: The correlation coefficient between X and Y is equal to (A) 07618 (B) 0.8342 (Two marks) (C) 0.9793 (D) None of them. Q42: The estimated regression equation of Y on X is (A) Y=2.7+2.1X (Two marks) (B)Ý 3.8+4.3X (C) Y-22-3.7X (D) None of them Q43: From the previous equation, the estimated value of Y when X-8 (One mark) (A) 38.2 (B) 19.5 (C) 13.9 (D) None of them 044: The coefficient of determination is equal to (One mark) (A) 0.9590 (B) 0.6959 (C) 0.5803 (D) None of them. Best Wishes for all Students Here are some tabulated values for different probability distributions: 21.28 10901.383 2.821 Zass-1.645 10st. 10 1.812 13.169 Χόκι - 6.64 Zawa-9.22 Zosts 1.96 10911.833 13.250 <=2.81 Zo-2.33 10977182.228 Ζώνος = 2.71 Fir-261 Z 2.58 12.262 Х=460 95F2.12-3.89 100101.372 11-2764 2 Χάκι -7.78 3,49 = ويرة روع