Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Statistical Methods > LECTURE 4 > Flashcards

LECTURE 4 Flashcards

1
Q

What is central tendency?

A

A single value representing a group of data, summarizing the dataset.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the two types of averages?

A
  1. Simple Averages: Mean, Median, Mode 2. Special Averages: Geometric Mean, Harmonic Mean.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the arithmetic mean (mean)?

A

The sum of all observations divided by the number of observations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the formula for mean for raw data?

A

Mean = Sum of observations ÷ Number of observations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the formula for mean for grouped data?

A

Mean = (Σ(f × x)) ÷ n.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the shortcut formula for mean?

A

Mean = A + (Σ(f × d)) ÷ n.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the merits of arithmetic mean?

A
  1. Simple to calculate 2. Rigidly defined 3. Reliable for large datasets 4. Basis for comparison.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the demerits of arithmetic mean?

A
  1. Sensitive to extreme values 2. Not suitable for qualitative data 3. Cannot handle open-end classes.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is the median?

A

The middle value in an ordered dataset.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How is the median calculated for raw data?

A
  1. If n is odd: Median = Middle value. 2. If n is even: Median = Mean of two middle values.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is the median calculated for grouped data?

A
  1. Find cumulative frequency. 2. Identify the median class. 3. Use the formula: Median = l + [(n/2 - m)/f] × c.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are the merits of median?

A
  1. Not influenced by extreme values 2. Handles open-end intervals 3. Useful for incomplete data.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the demerits of median?

A
  1. Affected by small changes in data 2. Not suitable for advanced calculations 3. Ignores other observations.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the mode?

A

The value that occurs most frequently in a dataset.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How is mode calculated for grouped data?

A
  1. Identify the modal class. 2. Use the formula: Mode = l + [(fm - fp) / (2fm - fp - fs)] × c.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the merits of mode?

A
  1. Represents the most typical value 2. Useful for qualitative data 3. Simple to understand.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the demerits of mode?

A
  1. May not exist 2. May have multiple values 3. Not suitable for mathematical analysis.
18
Q

What is the geometric mean (GM)?

A

The n-th root of the product of all observations.

19
Q

What is the formula for GM for grouped data?

A

GM = Antilog(Σ(f × log x) ÷ n).

20
Q

What are the uses of GM?

A
  1. Growth rates 2. Bacterial growth 3. Economic studies.
21
Q

What is the harmonic mean (HM)?

A

The reciprocal of the arithmetic mean of reciprocals of observations.

22
Q

What is the formula for HM?

A

HM = n ÷ Σ(1/x).

23
Q

What are the merits of HM?

A
  1. Ideal for rates and speeds 2. Weighted toward smaller values 3. Defined for all observations.
24
Q

What are the demerits of HM?

A
  1. Difficult to compute 2. Rarely used for grouped data 3. Not easily understood.
25
Q

What are percentiles?

A

Values dividing a dataset into 100 equal parts, each containing 1% of observations.

26
Q

What are quartiles?

A

Values dividing a dataset into 4 equal parts (Q1, Q2, Q3).

27
Q

How is the 25th percentile (Q1) calculated for grouped data?

A

Q1 = l + [(n/4 - m)/f] × c.

28
Q

How is the 75th percentile (Q3) calculated for grouped data?

A

Q3 = l + [(3n/4 - m)/f] × c.

29
Q

What are the steps to calculate quartiles for grouped data?

A
  1. Find cumulative frequency. 2. Identify Q1 and Q3 classes. 3. Use respective formulas.
30
Q

What is the difference between mean, median, and mode?

A

Mean: Arithmetic average. Median: Middle value. Mode: Most frequent value.

31
Q

Define central tendency with examples.

A

A central value summarizing data, e.g., mean, median, mode.

32
Q

The middle value of an ordered series is called what?

A

2nd quartile, 5th decile, or 50th percentile.

33
Q

For a set of values, the mode can be what?

A

Unimodal, bimodal, or trimodal.

34
Q

Is mode suitable for qualitative data?

A

Yes, it is suitable.

35
Q

What does deciles divide the group into?

A

Ten equal parts.

36
Q

Is the mean affected by extreme values?

A

Yes, it is affected.

37
Q

Can geometric mean be calculated for negative values?

A

No, it cannot.

38
Q

What type of data is mode used for?

A

Both qualitative and quantitative data.

39
Q

How do you calculate arithmetic mean for raw data?

A

Sum all values and divide by the number of observations.

40
Q

How do you calculate the median for grouped data?

A

Find cumulative frequencies and use the median formula.

41
Q

How do you calculate the mode for grouped data?

A

Use the modal class and the mode formula.

Statistical Methods (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions