Discriminant Analysis

🏥 Health Sciences · Discriminant Analysis

Discriminant Analysis

Modern · Sınıflandırma
🆕 New in v1.0.5: A Chart tab was added to this analysis (boxplot, interaction, profile, bar, scatter, biplot, or forecast — depending on analysis type).

Discriminant Analysis is one of the statistical analyses applied automatically in MerQur. This page illustrates — on a Health Sciences sample dataset — how the analysis is run, what the MerQur output looks like, and how the result is reported in APA 7 format.

🎯 What is it for?

Discriminant Analysis automatically performs all assumption checks required for the data type (normality, homogeneity of variance, etc.) in the background and presents the results in a clear table + chart. Automatic APA 7-formatted interpretation, effect sizes (Cohen’s d, η², R²) and 95% confidence intervals are reported.

📌 When is it used?

  • Statistical analysis of measurements in the Health Sciences domain
  • To produce APA 7-compatible result tables for academic publications
  • Hypothesis testing and decision-making processes
  • Undergraduate / master’s / PhD theses after the appropriate method has been selected

📐 Assumptions

  • Appropriate scale — Variables must be at the measurement level required by the analysis (nominal/ordinal/interval/ratio)
  • Independent observations — Observations must come from individuals independent of one another
  • Sufficient sample size — The minimum n requirement for the analysis must be met
  • Outlier check — Outliers must be detected and evaluated

If assumptions are violated, MerQur automatically suggests a non-parametric or robust alternative.

🛠 How to do it in MerQur

1

Load the data. Select the sample file from File → Open. MerQur auto-detects column types.

2

Select the analysis. From the left side select Discriminant Analysis.

3

Panel assignments (form fields in the program):

  • Target Column: sinif
  • Prediktorler: ['WBC_K_uL', 'CRP_mg_L', 'kreatinin', 'AST_U_L', 'Hb_g_dL']
  • Yontem: lda
  • CV kati: 5
4

Optional settings. Effect size ✓ · 95% confidence interval ✓ · Assumption checks (automatic).

5

▶ Run — click the button. Results are produced automatically as a table + chart.

6

📄 Export to Word. APA 7-formatted report with italic statistical symbols.

📊 Sample Dataset — Health Sciences

ℹ Note: The scenario, MerQur output and interpretation below were produced by actually running the real example dataset in MerQur. Numeric results on your own data will differ; the goal is to show how the analysis is set up and interpreted end-to-end.

🎬 Example File

This analysis is demonstrated on the following example dataset for Health Sciences:

Tip/84_diskriminant_3sinif_5lab.xlsx

🎬 Scenario

We classify patient class from five laboratory measures. To assign to predefined diagnostic classes, discriminant analysis is appropriate.

⚙️ Variable Selection

  • Dependent variable: class
  • Predictor(s): WBC_K_uL
  • Predictor(s): CRP_mg_L
  • Predictor(s): creatinine
  • Predictor(s): AST_U_L
  • Predictor(s): Hb_g_dL

Data Preview (First 5 Rows)

patient_idWBC_K_uLCRP_mg_LcreatinineAST_U_LHb_g_dLclass
19.36.00.992613.0healthy
27.56.10.922114.7healthy
36.15.70.942312.8healthy
47.64.90.962913.1healthy
57.85.00.83013.6healthy

n = 105 · Columns: patient_id, WBC_K_uL, CRP_mg_L, creatinine, AST_U_L, Hb_g_dL, class

📈 MerQur Output

DISCRIMINANT ANALYSIS RESULT ───────────────────────────────────────────── Accuracy = 1.00 outcome: class predictors: WBC_K_uL, CRP_mg_L, creatinine, AST_U_L, Hb_g_dL

💬 Interpretation

We classified patient class from five laboratory measures with discriminant analysis: accuracy 100% — the classes are fully separable with these markers (overfitting risk should be checked via cross-validation). Discriminant analysis finds the linear combinations that best separate groups; it both classifies and shows which marker is most influential in separation. In medicine it is used to assign new patients to predefined diagnostic classes and to identify discriminating laboratory markers.

⚠ Common Mistakes

  • Misidentifying the data type (e.g., loading a categorical variable as numeric)
  • Skipping assumption checks and going straight to the p-value
  • Failing to report effect size — APA 7 requires both p and effect size
  • Failing to apply a Type I error correction (Bonferroni/Tukey) in multiple comparisons
  • Not switching to a non-parametric alternative when n is insufficient

📹 Video Walkthrough

Watch the video below for an end-to-end walkthrough of this analysis on a Health Sciences file.

▶ Discriminant Analysis — video walkthrough

A complete end-to-end walkthrough of this analysis in MerQur, narrated on screen. Narration is in Turkish.

▶ Watch the video 📺 All videos

📚 If You Used This Analysis, Cite MerQur

If you performed this analysis using MerQur in a scientific study, please use the citation below as part of your academic citation obligations (APA 7):

Örücü, Ö. K. (2026). MerQur: Integrated Academic Data Analysis & Reporting Platform [Computer software] (Version 1.0.0). https://doi.org/10.53463/merqur.2026001

For BibTeX, RIS, EndNote and the English citation form: all citation formats →

Sources:
  1. American Psychological Association. (2020). Publication manual of the American Psychological Association (7th ed.).
  2. Field, A. (2018). Discovering statistics using IBM SPSS Statistics (5th ed.). Sage.
  3. Cohen, J. (1988). Statistical power analysis for the behavioral sciences (2nd ed.). Lawrence Erlbaum.