(LAB 1) Output numbers in reverse

Write a program that reads a list of integers, and outputs those integers in reverse. The input begins with an integer indicating the number of integers that follow. For coding simplicity, follow each output integer by a space, including the last one. Assume that the list will always contain fewer than 20 integers.

Ex: If the input is:

5 2 4 6 8 10

the output is:

10 8 6 4 2

To achieve the above, first read the integers into an array. Then output the array in reverse.

(LAB 2) Middle Item

 

Given a sorted list of integers, output the middle integer. Assume the number of integers is always odd.

Ex: If the input is:

2 3 4 8 11 -1 

(where a negative indicates the end), the output is:

4

The maximum number of inputs for any test case should not exceed 9. If exceeded, output “Too many inputs”.

Hint: First read the data into an array. Then, based on the array’s size, find the middle item.

(LAB 3) Output values below an amount

 

Write a program that first gets a list of integers from input. The input begins with an integer indicating the number of integers that follow. Then, get the last value from the input, which indicates a threshold. Output all integers less than or equal to that last threshold value. Assume that the list will always contain fewer than 20 integers.

Ex: If the input is:

5 50 60 140 200 75 100

the output is:

50 60 75

The 5 indicates that there are five integers in the list, namely 50, 60, 140, 200, and 75. The 100 indicates that the program should output all integers less than or equal to 100, so the program outputs 50, 60, and 75.

For coding simplicity, follow every output value by a space, including the last one.

Such functionality is common on sites like Amazon, where a user can filter results.

(LAB 4) Adjust list by normalizing

 

When analyzing data sets, such as data for human heights or for human weights, a common step is to adjust the data. This can be done by normalizing to values between 0 and 1, or throwing away outliers.

For this program, adjust the values by subtracting the smallest value from all the values. The input begins with an integer indicating the number of integers that follow. Assume that the list will always contain fewer than 20 integers.

Ex: If the input is:

5 30 50 10 70 65

the output is:

20 40 0 60 55

The 5 indicates that there are five values in the list, namely 30, 50, 10, 70, and 65. 10 is the smallest value in the list, so is subtracted from each value in the list.

For coding simplicity, follow every output value by a space, including the last one.

(LAB 5) Word Frequencies

 

Write a program that reads a list of words. Then, the program outputs those words and their frequencies. The input begins with an integer indicating the number of words that follow. Assume that the list will always contain fewer than 20 words.

Ex: If the input is:

5 hey hi Mark hi mark

the output is:

hey 1
hi 2
Mark 1
hi 2
mark 1

Hint: Use two arrays, one array for the strings and one array for the frequencies.

(LAB 6) Contains the character

 

Write a program that reads an integer, a list of words, and a character. The integer signifies how many words are in the list. The output of the program is every word in the list that contains the character at least once. Assume at least one word in the list will contain the given character. Assume that the list of words will always contain fewer than 20 words.

Ex: If the input is:

4 hello zoo sleep drizzle z

then the output is:

zoo
drizzle

To achieve the above, first read the list into an array. Keep in mind that the character ‘a’ is not equal to the character ‘A’.

(LAB 7) Elements in a range

 

Write a program that first gets a list of integers from input. The input begins with an integer indicating the number of integers that follow. Assume that the list will always contain fewer than 20 integers.

That list is followed by two more integers representing lower and upper bounds of a range. Your program should output all integers from the list that are within that range (inclusive of the bounds). For coding simplicity, follow each output integer by a space, even the last one. The output ends with a newline.

Ex: If the input is:

5 25 51 0 200 33
0 50

then the output is:

25 0 33 

(the bounds are 0-50, so 51 and 200 are out of range and thus not output).

To achieve the above, first read the list of integers into an array.

(LAB 8) Two smallest numbers

 

Write a program that reads a list of integers, and outputs the two smallest integers in the list, in ascending order. The input begins with an integer indicating the number of integers that follow. You can assume that the list will have at least 2 integers and fewer than 20 integers.

Ex: If the input is:

5 10 5 3 21 2

the output is:

2 3

To achieve the above, first read the integers into an array.

Hint: Make sure to initialize the second smallest and smallest integers properly.

A clinical trial is conducted to evaluate the efficacy of a new drug for prevention of

hypertension in patients with pre-hypertension (defined as systolic blood pressure between

120–139 mmHg or diastolic blood pressure between 80–89 mmHg). A total of 20 patients are

randomized to receive the new drug or a currently available drug for treatment of high blood

pressure. Participants are followed for up to 12 months, and time to progression to

hypertension is measured. The experiences of participants in each arm of the trial are shown

below.

data is on the document. the first one

 

To answer the question as to whether or not there is a difference in time to progression, a

Chi square statistic is computed. The critical value for rejection of the null hypothesis is

3.84. The computed Chi square is 0.335.

Based on comparing the computed Chi square and the critical Chi square, which of the

following is (are) true?

A. There is not statistically significant evidence to show that the time to progression is

different between groups.

B. There is statistically significant evidence to show that the time to progression is

different between groups.

C. The time to progression is essentially the same for each group.

D. a and c.

The hazard ratio risk of progression to hypertension is 0.658. Based on this computation,

which of the following is (are) true?

A. The risk of progression to hypertension is reduced by 34.2% in patients assigned

to the new drug as compared to the currently available drug.

B. The risk of progression to hypertension is 1.52 times higher in patient’s current

drug as compared to the new drug.

C. The risk of progression to hypertension is 5.12 times higher in patient’s current

drug as compared to the new drug

D. a and b

2. A clinical trial is conducted to evaluate the efficacy of a new drug for prevention of hypertension in patients with pre-hypertension (defined as systolic blood pressure between 120–139 mmHg or diastolic blood pressure between 80–89 mmHg). A total of 20 patients are randomized to receive the new drug or a currently available drug for treatment of high blood pressure. Participants are followed for up to 12 months, and time to progression to hypertension is measured. The experiences of participants in each arm of the trial are shown below.

 

New Drug		Currently Available Drug
Hypertension	Free of Hypertension		Hypertension	Free of Hypertension
7	8		6	8
8	8		7	9
10	8		9	11
	9		10	11
	11		11	12
	12
	12

 

 

Estimate the survival (time to progression to hypertension) functions for each treatment group using the Kaplan-Meier approach New Drug

Complete the table below.

 

Time, Months	Number at Risk Nt	Number of Events (Hypertension) Dt	Number Censored Ct	Survival Probability St+1 = St*((Nt-Dt)/Nt)
0	10	0
7		1
8		1
9		0
10		1
11		0
12		0

 

 

Currently Available Drug

Complete the table below.

 

Time, Weeks	Number at Risk Nt	Number of Events (Hypertension) Dt	Number Censored Ct	Survival Probability St+1 = St*((Nt-Dt)/Nt)
0	10
6
7
8
9
10
11
12

 

 

 

To answer the question as to whether or not there is a difference in time to progression, a Chi square statistic is computed. The critical value for rejection of the null hypothesis is 3.84. The computed Chi square is 0.335.

 

Based on comparing the computed Chi square and the critical Chi square, which of the following is (are) true?

 

A. There is not statistically significant evidence to show that the time to progression is different between groups.

B. There is statistically significant evidence to show that the time to progression is different between groups.

C. The time to progression is essentially the same for each group.

D. a and c.

 

The hazard ratio risk of progression to hypertension is 0.658. Based on this computation, which of the following is (are) true?

 

A. The risk of progression to hypertension is reduced by 34.2% in patients assigned to the new drug as compared to the currently available drug.

B. The risk of progression to hypertension is 1.52 times higher in patient’s current drug as compared to the new drug.

C. The risk of progression to hypertension is 5.12 times higher in patient’s current drug as compared to the new drug

D. a and b

 

 

The mean BMI in patients free of diabetes was reported as 28.2.  The investigator conducting the study  hypothesizes that the BMI in patients free of diabetes is higher.  Based on the data given below is there evidence that the BMI is significantly higher that 28.2?  Use a 5% level of significance.     25 27 31 33 26 28 38 41 24 32 35 40Critical t value:                  (2 points)Computed t =          (2 points)Based on comparing the critical t value to the computed t value which of the following is (are) true?

a. There is statistically significant evidence at alpha=0.05 to show the BMI is significantly higher than 28.2.  b. There is not  statistically significant evidence at alpha=0.05 to show the BMI is significantly     higher that 28.2.  c. There are not enough data points to reach a conclusion.d. b and c.

 

A randomized controlled trial is run to evaluate the effectiveness of a new drug for asthma in children. A total of 250 children are randomized to either the new drug or placebo (125 per group).  The mean age of children assigned to the new drug is 12.4 with a standard deviation of 3.6 years.  The mean age of children assigned to the placebo is 13.0 with a standard deviation of 4.0 years.  Is there a statistically significant difference in ages of children assigned to the treatments?  Apply the two sample z test at a 5% level of significance.

1. Critical z value = +/-                          (2 points)

2. Computed statistic=                         (2 points)

3. Based on comparing the computed statistic to the critical value which of the following is (are) true? (6 points)

a. There is significant evidence, alpha=0.05, that there is a difference in ages of children assigned to the treatments.

b. There is not significant evidence, alpha=0.05, that there is a difference in ages of children assigned to the treatments.

c. Statistically speaking the difference in initial weights and weights after 6 weeks is 0.

d. b and c.

 

A small pilot study is conducted to investigate the effect of a nutritional supplement on total body weight.  Six participants agree to take the nutritional supplement.  To assess its effect on body weight, weights are measured before starting the supplementation and then after 6 weeks.  The data are shown below.  Is there a significant increase in body weight following supplementation?  Use a paired t-test at a 5% level of significance.

1. df=_____ (2 points)

2. Critical value: ______  (2 points)

3. Computed statistic:_____ (2 points)

4. Based on comparing the computed statistic to the critical value which of the following is (are) true? (4 points)

a. There is significant evidence, alpha=0.05, to show that body weight increased following supplementation?

b. There is not significant evidence, alpha=0.05, to show that body weight increased following supplementation?

c. Statistically speaking the difference in initial weights and weights after 6 weeks is 0.

d. b and c.

 

A study is designed to investigate whether there is a difference in response to various treatments in patients with rheumatoid arthritis.  The outcome is patient’s self-reported effect of treatment.  The data are shown below.  Is there a statistically significant difference in the proportions of patients who show improvement between treatments 1 and 2.  Apply the test at a 5% level of significance.

1. Critical value:                           (2 points)

2. Computed statistic:                  (2 points)

3. Based on comparing the computed statistics to the critical value which of the following is (are) true? (6 points)

a. There is significant evidence, alpha=0.05, to show that there is a difference in the proportions of patients who show improvement between treatments 1 and 2.

b. There is not significant evidence, alpha=0.05, to show that there is a difference in the proportions of patients who show improvement between treatments 1 and 2.

c. There is significant evidence, alpha=0.05, to show that there is a no difference in the proportions of patients who show improvement between treatments 1 and 2.

d. a and c.

 

A randomized controlled trial is run to evaluate the effectiveness of a new drug for asthma in children. A total of 250 children are randomized to either the new drug or placebo (125 per group).  There are 63 boys assigned to the new drug group and 58 boys assigned to the placebo.  Is there a statistically significant difference in the proportions of boys assigned to the treatments?  Apply the appropriate test at a 5% level of significance.1. Critical value= +/-                             (2 points)2. Computed statistics=                       (2 points)3. Based on comparing the computed statistic to the critical value which of the following is (are) true?  (6 points)

a. There is significant evidence, alpha=0.05, that there is a difference in the proportions of boys assigned to the treatments.b. There is not significant evidence, alpha=0.05, that there is a difference in the proportions of boys assigned to the treatments.c. Statistically speaking the difference in the proportions of boys assigned to the treatments is 0.d. b and c.

 

 

The following data were collected in a clinical trial to compare a new drug to a placebo for its effectiveness in lowering total serum cholesterol.  Generate a 95% confidence interval for the difference in mean total cholesterol levels between treatments.

1. Upper limit of CI:                 (2 points)

2. Lower limit of CI:                 (2 points)

3. Based on the confidence interval which of the following is (are) true? (4 points)

a. There is significant evidence, alpha=0.05, to show that there is a difference in Total Serum Cholesterol between treatments New Drug and Placebo.

b. There is not significant evidence, alpha=0.05, to show that there is a difference in Total Serum Cholesterol between treatments New Drug and Placebo.

c. The difference between Total Serum Cholesterol between treatments New Drug and Placebo is essentially 0.

d. b and c.