def test_without_item_excludes(self): data = { "student_list": [{ "id": 1, "item_responses": [ { "item_id": 1, "response": 1 }, { "item_id": 2, "response": 0 }, ] }, { "id": 1, "item_responses": [{ "item_id": 1, "response": 1 }] }] } expected = [1, 2] id_list = utils.get_item_ids(data) assert id_list == expected
def test_with_item_excludes(self): data = { "student_list": [{ "id": 1, "item_responses": [{ "item_id": "1", "response": 1 }, { "item_id": "2", "response": 0 }, { "item_id": "3", "response": 1 }, { "item_id": "4", "response": 0 }] }, { "id": 2, "item_responses": [{ "item_id": "1", "response": 1 }] }], "exclude_items": ["4"] } expected = ["1", "2", "3"] id_list = utils.get_item_ids(data) assert id_list == expected
def get_assumptions(param): """ A function to get the items for which a student was assumed to have a response of 0: It gets a list of all item ids listed from every student's responses, then iterates through every student. If a student doesn't have a response for an item in the id list, then that item is assumed to have a response of 0 for that student. :param: a json in the Reliabilty Measures standard json format :return: a dictionary of dictionaries: a dictionary with student ids as keys and a list of item ids as values """ service_key = get_service_config(13) catch_error = get_error(param) if catch_error[0]: return {service_key: catch_error[1]} inp = update_input(param) student_list = get_student_list(inp) id_list = get_item_ids(inp) assumptions_dict = {} for i in student_list: # For each student i checklist = id_list.copy() dupes = [] for k in i[get_keyword_value("item_responses")]: # For each question k for j in id_list: # For each item ID j if k[get_keyword_value("item_id")] == j: # If item IDs match if j in checklist: checklist.remove(j) else: dupes.append(j) if dupes: assumptions_dict[i[get_keyword_value("id")]] = {} assumptions_dict[i[get_keyword_value("id")]][get_keyword_value( "dupes")] = dupes if len(checklist) != 0: assumptions_dict[i[get_keyword_value("id")]] = {} assumptions_dict[i[get_keyword_value("id")]][get_keyword_value( "assumed")] = checklist.copy() if not assumptions_dict: return {service_key: get_keyword_value("no_assumptions")} return {service_key: assumptions_dict}
def calculate_difficulty(param): """ A function to get the difficulty of each item on the exam: It calculates how many students got an item correct, and then divides it by the total number of students. :param: a json in the Reliabilty Measures standard json format :return: a dictionary of floats: a dictionary with item ids as keys and the difficulty as values """ service_key = get_service_config(3) catch_error = get_error(param) if catch_error[0]: return {service_key: catch_error[1]} inp = update_input(param) sorted_resp = get_sorted_responses(inp) num_students = len(sorted_resp) num_items = len(sorted_resp[0]) id_list = get_item_ids(inp) difficulty_list = [] difficulty_dict = {} for i in range(0, num_items): # For each question i numRight = 0 for k in range(0, num_students): # For each student k studentAnswer = sorted_resp[k][i] numRight += studentAnswer difficulty = 1 - numRight / num_students difficulty = round(difficulty, 3) difficulty_list.append(difficulty) k = 0 for i in id_list: difficulty_dict[i] = difficulty_list[k] k += 1 return {service_key: difficulty_dict}
def calculate_idr(param): """ A function to get the idr of each item: For every item, it calculates the mean score of students who got the answer right and subtracts it by the mean score of those who got it wrong. Then it multiplies that by the square root of the number of students who got the item right multiplied by the total of those who got it wrong. Then it divides that by the number of students multiplied by the std of the students' scores. :param: a json in the Reliabilty Measures standard json format :return: a dictionary of floats: a dictionary with item ids as keys and idr as values """ service_key = get_service_config(2) catch_error = get_error(param) if catch_error[0]: return {service_key: catch_error[1]} inp = update_input(param) sorted_resp = get_sorted_responses(inp) num_students = len(sorted_resp) num_items = len(sorted_resp[0]) id_list = get_item_ids(inp) score_std = get_score_std(inp) idr_list = [] idr_dict = {} if score_std < 0: return {service_key: get_keyword_value("bad_std")} for i in range(0, num_items): # For each question i right_list = [] wrong_list = [] num_right = 0 num_wrong = 0 for k in range(0, num_students): # For each student k if sorted_resp[k][i] == 1: # If student k gets question i correct score = sum(sorted_resp[k]) / num_items right_list.append( score) # Then add their score to the "right" list num_right += 1 elif sorted_resp[k][i] == 0: # If student k gets question i wrong score = sum(sorted_resp[k]) / num_items wrong_list.append( score) # Then add their score to the "wrong" list num_wrong += 1 if num_right == num_students or num_wrong == num_students: idr_list.append(0) continue if len(right_list) == 1: right_mean = right_list[0] elif len(right_list) > 1: right_mean = mean(right_list) if len(wrong_list) == 1: wrong_mean = wrong_list[0] elif len(wrong_list) > 1: wrong_mean = mean(wrong_list) if not right_mean or not wrong_mean: return {service_key: get_keyword_value("bad_mean")} idr = ((right_mean - wrong_mean) * sqrt(num_right * num_wrong)) / num_students * score_std idr = round(idr, 3) idr_list.append(idr) k = 0 for i in id_list: idr_dict[i] = idr_list[k] k += 1 return {service_key: idr_dict}
def test_get_item_ids(self): expected = ["1", "2", "3", "4", "5", "6", "7", "8"] item_ids = utils.get_item_ids(self.data) assert item_ids == expected