Skip to main content

Tight Inapproximability of Minimum Maximal Matching on Bipartite Graphs and Related Problems

  • Conference paper
  • First Online:
Approximation and Online Algorithms (WAOA 2021)

Abstract

We study the Minimum Maximal Matching problem, where we are asked to find in a graph the smallest matching that cannot be extended. We show that this problem is hard to approximate with any constant smaller than 2 even in bipartite graphs, assuming either of two stronger variants of Unique Games Conjecture. The bound also holds for computationally equivalent Minimum Edge Dominating Set. Our lower bound matches the approximation provided by a trivial algorithm.

Our results imply conditional hardness of approximating Maximum Stable Matching with Ties and Incomplete Lists with a constant better than \(\frac{3}{2}\), which also matches the best known approximation algorithm.

Supported by Polish NSC grants 2018/29/B/ST6/02633 and 2015/18/E/ST6/00456.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 49.99
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 64.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Notes

  1. 1.

    To illustrate that imagine a cycle of four edges with weights (1, 1, 100, 100). The lightest EDS weighs 2, but MMM must contain two opposite edges and weighs 101.

  2. 2.

    The inapproximation ratio claimed in the original work [10] is 1.18, which follows from a reduction from Vertex Cover. However, due to the recent improvement in NP-hardness of approximating the latter problem [7, 8, 16], the inapproximation ratio for EDS improves to 1.207.

  3. 3.

    This formulation is slightly different that the original one from [15], but the two formulations are known to be equivalent [17].

  4. 4.

    Originally, Strong UGC was used to refer to an equivalent formulation of UGC [17]. Here we follow the nomenclature of [3], which refers to Conjecture 2 as Strong UGC.

  5. 5.

    This is similar to Strong UGC except that Strong UGC deals with vertex expansion whereas SSEH concerns with edge expansion.

  6. 6.

    These results talk about Balanced Biclique which is more natural, but since bi-independent set fits our needs more, we will silently take graph complement when recalling their reductions.

  7. 7.

    The character ‘\(\circ \)’ is a function composition operator. Since a vector can be viewed as a function mapping indices to values, for a permutation \(\pi \) and a vector x, \(\pi \circ x\) is the vector with permuted elements.

  8. 8.

    (AB) is a bisection of X if \(|A| = |B| = |X|/2\) and \(A \cup B = X\).

  9. 9.

    The vectors \(\mathbf {v}\) and \(\mathbf {w}\) are neighbours in \(G^{\otimes R}\) iff \(v_i\) is connected to \(w_i\) in G for every \(i\in [R]\).

  10. 10.

    Equivalently we will write that \(\pi ^{1,\dots ,k}(\mathbf {u})\) and \(\mathbf {v}\) are neighbours in \(G^{\otimes (R\times k)}\).

  11. 11.

    This may be not unique. The choice of a permutation is arbitrary.

  12. 12.

    \(T_0\) and \(T_1\) are called \(T'_0\) and \(T'_1\) respectively in [20].

References

  1. Austrin, P., Pitassi, T., Wu, Yu.: Inapproximability of treewidth, one-shot pebbling, and related layout problems. In: Gupta, A., Jansen, K., Rolim, J., Servedio, R. (eds.) APPROX/RANDOM -2012. LNCS, vol. 7408, pp. 13–24. Springer, Heidelberg (2012). https://doi.org/10.1007/978-3-642-32512-0_2

    Chapter  MATH  Google Scholar 

  2. Bansal, N., Khot, S.: Optimal long code test with one free bit. In: 50th Annual IEEE Symposium on Foundations of Computer Science, FOCS 2009, Atlanta, Georgia, USA, 25–27 October 2009, pp. 453–462. IEEE Computer Society (2009)

    Google Scholar 

  3. Bhangale, A., Gandhi, R., Hajiaghayi, M.T., Khandekar, R., Kortsarz, G.: Bicovering: covering edges with two small subsets of vertices. In: Chatzigiannakis, I., Mitzenmacher, M., Rabani, Y., Sangiorgi, D. (eds.) 43rd International Colloquium on Automata, Languages, and Programming, ICALP 2016, Rome, Italy, 11–15 July 2016, vol. 55 of LIPIcs, pp. 6:1–6:12. Schloss Dagstuhl - Leibniz-Zentrum für Informatik (2016)

    Google Scholar 

  4. Carr, R.D., Fujito, T., Konjevod, G., Parekh, O.: A 2 1/10-approximation algorithm for a generalization of the weighted edge-dominating set problem. In: Paterson, M.S. (ed.) ESA 2000. LNCS, vol. 1879, pp. 132–142. Springer, Heidelberg (2000). https://doi.org/10.1007/3-540-45253-2_13

    Chapter  Google Scholar 

  5. Charikar, M., Chatziafratis, V.: Approximate hierarchical clustering via sparsest cut and spreading metrics. In: Klein, P.N. (ed.) Proceedings of the Twenty-Eighth Annual ACM-SIAM Symposium on Discrete Algorithms, SODA 2017, Barcelona, Spain, Hotel Porta Fira, 16–19 January 2017, pp. 841–854. SIAM (2017)

    Google Scholar 

  6. Chlebík, M., Chlebíková, J.: Approximation hardness of edge dominating set problems. J. Comb. Optim. 11(3), 279–290 (2006)

    Article  MathSciNet  Google Scholar 

  7. Dinur, I., Khot, S., Kindler, G., Minzer, D., Safra, M.: On non-optimally expanding sets in grassmann graphs. In: Diakonikolas, I., Kempe, D., Henzinger, M. (eds.) Proceedings of the 50th Annual ACM SIGACT Symposium on Theory of Computing, STOC 2018, Los Angeles, CA, USA, 25–29 June 2018, pp. 940–951. ACM (2018)

    Google Scholar 

  8. Dinur, I., Khot, S., Kindler, G., Minzer, D., Safra, M.: Towards a proof of the 2-to-1 games conjecture? In: Diakonikolas, I., Kempe, D., Henzinger, M. (eds.) Proceedings of the 50th Annual ACM SIGACT Symposium on Theory of Computing, STOC 2018, Los Angeles, CA, USA, 25–29 June 2018, pp. 376–389. ACM (2018)

    Google Scholar 

  9. Dudycz, S., Lewandowski, M., Marcinkowski, J.: Tight approximation ratio for minimum maximal matching. In: Lodi, A., Nagarajan, V. (eds.) IPCO 2019. LNCS, vol. 11480, pp. 181–193. Springer, Cham (2019). https://doi.org/10.1007/978-3-030-17953-3_14

    Chapter  Google Scholar 

  10. Escoffier, B., Monnot, J., Paschos, V.T., Xiao, M.: New results on polynomial inapproximability and fixed parameter approximability of edge dominating set. In: Thilikos, D.M., Woeginger, G.J. (eds.) IPEC 2012. LNCS, vol. 7535, pp. 25–36. Springer, Heidelberg (2012). https://doi.org/10.1007/978-3-642-33293-7_5

    Chapter  MATH  Google Scholar 

  11. Fujito, T., Nagamochi, H.: A 2-approximation algorithm for the minimum weight edge dominating set problem. Disc. Appl. Math. 118(3), 199–207 (2002)

    Article  MathSciNet  Google Scholar 

  12. Gotthilf, Z., Lewenstein, M., Rainshmidt, E.: A \((2 - c \frac{\log {n}}{n})\) approximation algorithm for the minimum maximal matching problem. In: Bampis, E., Skutella, M. (eds.) WAOA 2008. LNCS, vol. 5426, pp. 267–278. Springer, Heidelberg (2009). https://doi.org/10.1007/978-3-540-93980-1_21

    Chapter  MATH  Google Scholar 

  13. Hardt, M., Moitra, A.: Algorithms and hardness for robust subspace recovery. In: Shalev-Shwartz, S., Steinwart, I. (eds.) COLT 2013 - The 26th Annual Conference on Learning Theory, Princeton University, NJ, USA, 12–14 June 2013, vol. 30 of JMLR Workshop and Conference Proceedings, pp. 354–375. JMLR.org (2013)

    Google Scholar 

  14. Huang, C.-C., Iwama, K., Miyazaki, S., Yanagisawa, H.: A tight approximation bound for the stable marriage problem with restricted ties. In: Garg, N., Jansen, K., Rao, A., Rolim, J.D.M. (eds.) Approximation, Randomization, and Combinatorial Optimization. Algorithms and Techniques, APPROX/RANDOM 2015, Princeton, NJ, USA, 24–26 August 2015, vol. 40 of LIPIcs, pp. 361–380. Schloss Dagstuhl - Leibniz-Zentrum für Informatik (2015)

    Google Scholar 

  15. Khot, S.: On the power of unique 2-prover 1-round games. In: Reif, J.H. (ed.) Proceedings on 34th Annual ACM Symposium on Theory of Computing, Montréal, Québec, Canada, 19–21 May 2002, pp. 767–775. ACM (2002)

    Google Scholar 

  16. Khot, S., Minzer, D., Safra, M.: Pseudorandom sets in grassmann graph have near-perfect expansion. In: Thorup, M. (ed.) 59th IEEE Annual Symposium on Foundations of Computer Science, FOCS 2018, Paris, France, 7–9 October 2018, pp. 592–601. IEEE Computer Society (2018)

    Google Scholar 

  17. Khot, S., Regev, O.: Vertex cover might be hard to approximate to within \(2-\epsilon \). J. Comput. Syst. Sci. 74(3), 335–349 (2008)

    Article  MathSciNet  Google Scholar 

  18. Khot, S., Vishnoi, N.K.: The unique games conjecture, integrality gap for cut problems and embeddability of negative-type metrics into \(\ell _1\). J. ACM 62(1), 8:1–8:39 (2015)

    Google Scholar 

  19. Louis, A., Raghavendra, P., Vempala, S.S.: The complexity of approximating vertex expansion. In: 54th Annual IEEE Symposium on Foundations of Computer Science, FOCS 2013, Berkeley, CA, USA, 26–29 October 2013, pp. 360–369. IEEE Computer Society (2013)

    Google Scholar 

  20. Manurangsi, P.: Inapproximability of maximum edge biclique, maximum balanced biclique and minimum k-cut from the small set expansion hypothesis. In: 44th International Colloquium on Automata, Languages, and Programming, ICALP 2017, Warsaw, Poland, 10–14 July 2017, pp. 79:1–79:14 (2017)

    Google Scholar 

  21. Parekh, O.: Edge dominating and hypomatchable sets. In: Eppstein, D. (ed.) Proceedings of the Thirteenth Annual ACM-SIAM Symposium on Discrete Algorithms, San Francisco, CA, USA, 6–8 January 2002, pp. 287–291. ACM/SIAM (2002)

    Google Scholar 

  22. Raghavendra, P., Steurer, D.: Graph expansion and the unique games conjecture. In: Schulman, L.J. (ed.) Proceedings of the 42nd ACM Symposium on Theory of Computing, STOC 2010, Cambridge, Massachusetts, USA, 5–8 June 2010, pp. 755–764. ACM (2010)

    Google Scholar 

  23. Raghavendra, P., Steurer, D., Tulsiani, M.: Reductions between expansion problems. In: Proceedings of the 27th Conference on Computational Complexity, CCC 2012, Porto, Portugal, 26–29 June 2012, pp. 64–73 (2012)

    Google Scholar 

  24. Schmied, R., Viehmann, C.: Approximating edge dominating set in dense graphs. Theor. Comput. Sci. 414(1), 92–99 (2012)

    Article  MathSciNet  Google Scholar 

  25. Yannakakis, M., Gavril, F.: Edge dominating sets in graphs. SIAM J. Appl. Math. 38(3), 364–372 (1980)

    Article  MathSciNet  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Jan Marcinkowski .

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2021 Springer Nature Switzerland AG

About this paper

Check for updates. Verify currency and authenticity via CrossMark

Cite this paper

Dudycz, S., Manurangsi, P., Marcinkowski, J. (2021). Tight Inapproximability of Minimum Maximal Matching on Bipartite Graphs and Related Problems. In: Koenemann, J., Peis, B. (eds) Approximation and Online Algorithms. WAOA 2021. Lecture Notes in Computer Science(), vol 12982. Springer, Cham. https://doi.org/10.1007/978-3-030-92702-8_4

Download citation

  • DOI: https://doi.org/10.1007/978-3-030-92702-8_4

  • Published:

  • Publisher Name: Springer, Cham

  • Print ISBN: 978-3-030-92701-1

  • Online ISBN: 978-3-030-92702-8

  • eBook Packages: Computer ScienceComputer Science (R0)

Publish with us

Policies and ethics